X-Rays Join the Fight Against Fakes

June 30, 2023

(Revised from an article first written on 14th October 2009)

One of the major problems for any dealer in manufactured items is getting the description right – whether the objects are expensive watches, motor vehicle parts or designer-label garments at ridiculously low prices. A stroll through any street market will provide plenty of evidence for fake or misleadingly described goods. Not everything is what it appears to be, and the old Roman tag of ‘caveat emptor’ (let the buyer beware) has never been more apt.

In the field of coins and antiquities there is plenty of scope for mistaken or misleading descriptions. The rewards for passing off modern fakes or forgeries as genuine ancient coins and artefacts can be very tempting. At TimeLine Auctions we have to be very careful never to offer for sale as genuine an object which is in any way ‘dubious’. This means that any items we place on our platform have been thoroughly researched, catalogued and vetted, which is a very expensive and time-consuming task, but an absolutely essential one if our customers are to be able to buy from us with complete confidence.

Research can mean several hours spent poring over reference books and archaeological reports, looking through back-issues of metal-detecting magazines and auction catalogues. The cost of this research can never be recouped through the sales price of the articles, but the cost of not doing enough research is that fakes or forgeries remain in the market, the forgers are encouraged to continue and collectors cannot be sure that the coveted items they buy are genuine.
But modern science can assist with weeding out fakes and forgeries. There have been many developments in dating techniques since the beginnings of science-based archaeology in the mid-20th century. X-ray Fluorescence (XRF), thermoluminescence, dendrochronology phentermine and carbon-dating are four of the better known techniques.

The principle behind XRF is quite simple: the item’s surface is bombarded with X-rays; these interact with the metal at the sub-atomic level, making it fluoresce (glow) and the wavelengths of the fluorescence are measured by the machine. The fluorescence pattern is different for every element present, so an accurate analysis of the composition can be made. The development of portable machines which can display the results on an integral screen is the real breakthrough – instead of having to take the sample into a controlled laboratory environment, prepare it and wait for the results, with modern machinery and computing power it is possible to discover the relative proportions (percentages) of the various elements present within a matter of minutes.

What this means for coin and antiquities dealers is that it is no longer necessary to rely on subjective judgements when evaluating an article. The look and feel are still important, but with XRF technology it is possible to add to these the results of objective analysis, to add defined quantities into the equation. Because XRF testing is completely non-destructive, it does not damage the item’s surface or even disturb the patina – the X-ray penetration is just a few atoms deep, totally invisible and without any effect on the article itself. This is especially useful when a highly sensitive and rare piece has to be evaluated – a few minutes with the XRF technician can provide objective data which can not only spot whether it is a fake or not, but can actually give impartial information to back up the technician’s opinion based on the test results. TimeLine has been using X-ray Fluorescence to help with authentication since the late 2000s. For a minimal cost and delay, an object with a price tag of hundreds or thousands of pounds can be evaluated. This is a sensible investment of time and money – especially where so much is at stake. Not only does a fake coin in a collection call into question the reliability of the dealer from whom it was purchased, it also raises queries about the judgement of the collector who accepted it.

Obviously, the XRF test results do not in themselves show an object to be genuine or false. The technician has to have some known genuine results with which to compare those from the piece being tested. As XRF testing is rolled out among collectors and dealers, the spotting of many fakes will become much easier. This will no doubt cause the serious forgers to raise their game in order to circumvent the technology. But for the majority of forgers it will cause insuperable problems which will make the enterprise unrewarding and thus unattractive. If collectors’ confidence in their purchases through reputable dealers is increased, this will in time drive out both the fakers and the dealers who do not ask too many awkward questions.

Brett Hammond

TimeLine Auctions

(This article was first published on 14th October 2009)

A TimeLine Auctions Guide to Artefact Testing and Validation

June 29, 2023

(Revised from an article first published in 2008)

It is impossible to judge if an antiquity is genuine or not by simply viewing an image. To make a judgement based on image alone is flawed and those that adopt such procedures do so unprofessionally. At TimeLine we employ various methods to ascertain if an item is genuine and in addition we employ a vetting committee of over ten qualified archaeologists and other specialists who meet for several days before every printed catalogue sale. Each of these professionals physically handles and studies all of the objects presented to us for the following auction. We do not accept any item for sale unless this vetting committee is unanimous in its dating and opinion regarding the object’s culture. 

The testing and validation of artefacts offered for sale by coin and antiquities dealers is an important aspect of the authentication of antiquities, identifying fakes and forgeries and determining the likely origin. Technicians employed by TimeLine Auctions can deploy a range of techniques to provide information from which we may form an opinion about an object, and this article summarises the operation of the more commonly used ones. 

Fakes and forgeries are a persistent problem for collectors and dealers, and the elimination of such spurious pieces from authoritative collections is in the interest of both groups and of the scholarly community. Misidentification of genuine artefacts is another problem. Investigation can be difficult and time-consuming, but is essential if our customers are to buy from us with complete confidence.

Laboratories are constantly seeking to maintain as wide a range of techniques and technologies as possible, therefore the techniques dealt within this guide may represent only a selection from among those actually in use. Many of these techniques are available through our in-house facilities.

Visual Appraisal

This is the first technique we use, and it is often the most useful. After years of studying genuine ancient artefacts, TimeLine’s specialists have developed a familiarity with the objects which helps in detecting when something does not look quite right. If so, we will use one of the following techniques to verify and cross-check.

Optical Microscopy

This technique involves the close examination of the surface of an object under powerful magnification. It is customary to use this as a preliminary exercise before progressing to the other techniques described here. The majority of faking and tampering can be detected using a good microscope and a practised eye. Fake surface patination which has been painted on to mask a repair or to impart a feeling of age to a reproduced object can easily be detected under the microscope. Additionally, genuine ancient objects which have been ‘upgraded’ with the addition of modern inlay to increase their value can be discovered.

Most periods of history have characteristic ‘signature’ technologies which are perhaps not hard to replicate to convince the naked eye, but which are easy to expose at high magnification. Microscopy has a further use in linking items produced from a single workshop. Where a particular tool has a slight deformity or irregularity and evidence for this can be found on several items, it is a reasonable deduction that these were all made with the same tool – and therefore they emanate from a single workshop, or from the hands of a single workman. Microscopy is also used when cleaning objects, to ensure that only adhesions and corrosion products are removed to stabilize the surface, and not the underlying structure. TimeLine Auctions is able to conduct this procedure with our in-house facilities.


Boroscopy is sometimes called Remote Visual Inspection (RVI). It involves inserting a miniaturized camera into an aperture in the object to discover information about its internal structure. The methods of manufacture used to produce an item can often be determined by this method, and compared with those used on known genuine artefacts of the same culture and period. We are able to conduct this procedure with our in-house facilities.

Chemical Testing

There are several forms of chemical testing which can be used to analyse the surface of an object without recourse to XRF technology. It is commonly used to test surface ‘corrosion products’ to determine whether they are genuine or have been applied later to artificially age the object, and to detect repairs such as metal fractures strengthened with modern solder. We are able to conduct this procedure with our in-house facilities.


The technique of metallography is used to determine the internal structure of a metallic object. Corrosion may be removed from the surface by mechanical means, but if the underlying chemical reactions which gave rise to it are not halted, the process will continue at a sub-surface level. This will weaken and degrade the object, and if left unchecked for long enough will result in its complete destruction. 

Metallography can often be performed where the surface of an object has been disturbed, without the need for further intrusive operations. It is an extension of optical microscopy which can give information about the composition and distribution of elements within the metal. In the case of copper-alloy material, the proportions of copper to other elements and their distribution within the metal can provide dating information when compared to other objects of the same period and culture. Needless to say, it can also be used to detect modern reproductions and ancient forgeries. Furthermore, the chemical changes which take place over decades or centuries are impossible to reproduce mechanically and where these are present at a microscopic level they indicate ancient metal. Several third party metal specialists offer this service.

X-Ray Fluorescence (XRF)

The XRF process is at the heart of modern metallurgical and elemental analysis. A tiny point on the surface of the object is bombarded with X-Rays at the atomic level, which causes the elements present to fluoresce (glow); the properties of the luminescence can be measured to determine which elements are present, and their relative proportions.

Technical developments in micro-processing have allowed XRF machines to be produced which can be bench-mounted or hand-held, and which can give results within minutes on a computer screen. This has allowed the process of testing to become faster and more efficient, and widened its potential applications. The process is entirely non-destructive and the material to be tested does not need any special preparation. The more sensitive machines can give results expressed as ‘parts per million’.

XRF by itself can only provide information about the material’s composition. Results obtained from an item have to be compared with results from other objects in order to establish with confidence that the item’s composition is consistent with material from a specific period. TimeLine is able to conduct this procedure with our in-house facilities.

Radiocarbon Dating

Radiocarbon dating is used to determine the age of organic materials such as wood, bone, ivory, shell, lacquer and antler. It is most useful on material less than about 50,000 years old; beyond that range, the results are less reliable. Radiocarbon (C14) is a naturally occurring radioactive isotope of carbon, far less common than the stable forms (C12 and C13); all three elements are absorbed by living things through interaction with their environment and through the food-chain. At death, further absorption of C14 ceases and gradually the unstable C14 begins to convert to the stable nitrogen (N14) at a known rate; in essence it takes 5730 years for half the C14 in an object to stabilise, known as its ‘half-life’. Comparison of the measured C14 content of an item with its stable carbon content allows an assessment of its age (i.e. the point at which it stopped absorbing C14 and the element began to stabilise). C14 results have to be adjusted due to variations in the amount of C14 in the atmosphere at given periods. Several third party laboratories offer this service.


Radiography (X-ray imaging) can be used to detect the internal structure of an object, and thus to determine whether it is whole or assembled from a number of pieces, whether it has suffered damage (and repair), and whether the construction is consistent with other examples from the originating culture and period. Standard medical X-ray equipment is not usually sufficiently penetrative to be used on archaeological materials. Several third party laboratories offer this service.


Thermoluminescence (TL) is a technique which can be used to date ceramic material. It relies upon bombarding the material with thermal energy to release trapped electrons; the freed electrons recombine with atoms and in doing so emit a photon (light particle). The light emitted by the clay upon heating is measured and compared to known emissions data from calibrated material, so it is possible to deduce the amount of radiation acquired by the material since it was fired. The quantity of radiation divided by a known rate of acquisition per year gives the number of years since the pottery was fired. For this process we use Oxford Authentication Ltd.

Ultraviolet Scanning

Ultraviolet Scanning (UVS) can be used to detect the presence of certain materials on an object’s surface – for example, epoxy or other adhesives used to repair breaks, alterations to the object’s appearance made with chemical dyes, re-touched areas. UVS is non-destructive and can be performed with hand-held equipment so that maximum coverage of complex shapes can be achieved. We are able to conduct this procedure with our in-house facilities.

X-Ray Diffraction

X-Ray Diffraction (XRD) is a technique, similar to XRF above, which can measure the diffraction pattern of a surface and thus supply information about the elements present; it is most useful for comparing surface treatments such as pottery glazes and pigments.
Several third party laboratories offer this service.


We hope that this guide has been useful in explaining some of the techniques we can use to authenticate artefacts we offer through our platform. As time progresses, new techniques become available and existing techniques are refined. TimeLine Auctions strives to keep abreast of current trends in the analysis of antiquities in order to ensure that all of our clients may make their purchases with the utmost confidence.

Brett Hammond

TimeLine Auctions

(Revised from an article first published in 2008)

Theft from Benghazi Bank

November 16, 2011

Further to our publication of the article on the Libyan situation, we now have permission to disseminate the following update.



More has emerged since this article was published in Antiques Trade Gazette. There were a large number of Byzantine and Islamic coins involved. What is missing in the Islamic coins is a large number of the Almoravid Dynasty. This stands to reason because it was this dynasty that ruled Libya (AD. 1062-1147). This is not exclusive. We should all be careful when handling any Islamic coins of what is to-day Libya.

UNESCO (www.unesco.org) is issuing lists of what is missing. However this is likely of necessity not to be complete. Readers will be kept up-dated. That said much of the missing property, not just coins but jewellery and other artifacts is unlisted. So, we must be diligent in any dealings with valium antiquities of any period which could come from Libya. It is worth noting that of course some of the antiquities and coins of this part of the world are “clean”. But diligence is the watch word.

Richard Falkiner


September 6, 2011

September 6, 2011

Recent developments in Libya, with the ousting of the Gadhafi regime, the installation of the temporary interim government (NTC) and the refusal of some Gadhafi supporters to relent, combine to make the situation highly volatile. The fate of Libya’s rich archaeological heritage hangs in the balance.
The sites are not all well known in the west, due to nearly half a century of diplomatic isolation. In the south of Libya, in Acacus, 12,000 years old rock paintings are found across an entire mountain range. In the east, the city of Cyrene was once given to Cleopatra by the Roman general Mark Antony. Along the coast, the splendid ruins of Leptis Magna were buried for centuries under the sand, and were said to be one of the most beautiful cities of the Roman Empire. Recent gun battles took place among the ruins, with unknown consequences.
The eventual fate of these sites is cast into doubt by the Gadhafi regime’s track record. Additionally, once the fighting has ceased, typically there may be groups of armed men in a position to take whatever they wish. Antiquities may appear an attractive proposition for looting and sale. This is understood alkready to have taken tramadol place in Benghazi, the country’s second city and the base from which the NTC launched its operations. The so-called ‘Treasure of Benghazi’ was removed from the bank vault where it was stored.
UNESCO is preparing to send in an assessment team to examine the damage to the sites as soon as it’s safe to do so, and there are plans for a large international meeting in October to explore the future of Libya’s archaeological sites.

UK Treasure Trove Act Changes

January 12, 2010

January 12, 2010

An amendment to the legal framework in the UK concerning finds which are classed as ‘treasure’ was passed on 12th November 2009. For the purposes of the law, ‘treasure’ means an object or group of objects more than 300 years old with more than 10 per cent gold or silver. There has for a long time been a legal duty to report finds of treasure to the authorities; a coroner will then conduct an inquest to determine wther the treasure was lost (and thus the property of the crown) or hidden with a view to recovery, in which case the coroner must try to trace the owner or any surviving legal heirs (and should non be found the treasure reverts to the crown).
The new law, incorporated in the ‘Coroners and Justice Bill 2009′, makes it the legal duty of the possessor of any item which is or might be treasure to report it within 14 days of acquiring it or becoming aware that it might be treasure. Previously the onus was on the finder of any such item, but now the duty of reporting (disclosure) rests with the person in possession of the item. This will obviously have implications for dealers who hold stocks of coins and antiquities with significant gold or silver content. The act applies to England and Wales, but the Scottish position is slightly different due to the automatic duty to dislose which already exists in that country.
The only defence in law appears to be (i) to demonstrate that the item is not treasure or (ii) to establish that the item has already been reported when acquired. Ignorance of the law is not a workable legal defence!
The act does allow for a defence that the defendant may have a reasonable excuse for online pharmacies failing to notify; until this is tested in court, there is no means of knowing what will qualify as a reasonable excuse.
The punishment for being found guilty of not reporting extends to up to 51 weeks’ imprisonment and / or a fine of up to GBP 5000.
While reporting of finds of antiquities (whether treasure or not) is a laudable aim, it seems likely that this change in the law will potentially capture many people who find objects while gardening, walking the dog, making sandcastles on the beach and so on. The case law established here will be interesting!

Museums’ Acquisition Policy

October 14, 2009

As publicly-funded bodies whose directors are accountable to central governments, European museums have to be especially careful when offering to purchase any items. In the litigious world of today, museums are often the target of groups who try to make political capital out of the fact that ancient artefacts and human remains from a variety of cultures are housed in these buildings for public display.
With the 19th century vogue for collecting among the gentry and wealthier citizens, several very important collections were established which have been sources of knowledge for subsequent generations of students. In the 20th century, especially in mainland Europe, in the turmoil of war many objects were removed from captured cities, both by the Axis powers and by the Soviets; it would be naive to think that the western Allies never indulged in this practice.
Before acquiring objects, musuems are now required to carry out ‘due diligence’, similar to what happens when one corporation offers ambien to acquire another. The aim of this process is to establish the ownership of the objects to be acquired, and to avoid embroiling the museum in any expensive, long-running, legally complex or politically embarassing disputes.
The guidelines in force in the United Kingdom are quite comprehensive, requiring the donor/seller to supply information concerning the known history and provenance of the object, including:

      • name of discoveror


      • date and place of discovery


      • circumstances of discovery


      • history of sales and catalogue listings


    • any relevant involvement by the authorities (e.g. Treasure Valuation Committee)

The donor/seller must sign a written statement confirming that he/she is the absolute beneficial owner of the object(s), free from third party claims and encumbrances, and offering to sell or donate the same to the museum, and that any information provided as to the provenance of the object(s) is correct to the best of his/her knowledge, information and belief. This applies even if the museum is not paying for the item, but is receiving a gift.
The curator of the receiving museum or institution must also be very careful, making a corresponding signed statement to the effect that he/she has made reasonable enquiries in respect of the acquisition (and summarizing them) and that there is no reason in the DCMS guidelines for combating illicit trade (October 2005), nor in the museum’s own acquisition policy, not to make the proposed acquisition.
The curator is obliged to look at the following areas when considering the proposed acquisition:

      • to examine at first hand and to consider the type of item and likely place of origin


      • to take expert advice in areas outside the the curator’s own expertise


      • to determine whether the item was lawfully exported to the United Kingdom in the case of items sourced from abroad, and to check whether the export of the item was in line with the regulations of the country of origin, and other cultural property legislation applicable at the time the item was exported.


      • to evaluate the account given of the provenance (including export) of the item provided by the owner


      • to consider whether any specific permissions are required from the country of origin


    • If in doubt do not proceed

Critically, failure of the curator to satisfy him/herself on any of these points means that the acquisition should not go ahead, and if he/she believes a criminal offence may have been committed, to report the matter to the Police.

These requirements obviously place a burden of responsibility on the seller, who will be obliged to provide detailed information about the source of the object, and on the museum staff members who decide to acquire.

Nighthawking at Rendlesham

October 14, 2009

‘Nighthawking’ is the illegal metal-detecting of sites and theft of finds, usually conducted under cover of darkness.
It is not only illegal, since it usually involves trespass, criminal damage and theft, but also highly destructive on sites which are of great importance to our understanding of the past. Until a site is ‘scheduled’ (officially recognized as of national importance, and designated as such) there are no penalties for removing material with the landowner’s permission. But many important sites are unrecognized – precisely because the thieves are looting them covertly and want to keep the locations secret.
Recent media coverage of a pending prosecution has highlighted the problem of Rendlesham, Suffolk, a site mentioned by Bede in the Historia Ecclesiastica Gentis Anglorum (III.22) as mansio rendili, the ‘house of Rendel’ or in old English Rendles ham, still the name of a village in east Suffolk. Bede’s mention of the site is in connection with the baptism of an East Saxon king during his stay with an East Anglian king. The implication is that Rendlesham was a royal site in the mid-7th century, and that it was an appropriate location for kings to entertain royal guests – a royal feasting hall, accommodation buildings, service buildings and an early church would seem to be the minimum one would expect to find here.
Despite such written documentation, the Rendlesham site has never been identified on the ground, and therefore it has never been scheduled. However, local landowner Sir Michael Bunbury applied to the County Council Archaeological Service about his Naunton Hall estate and the damage done to his property by nocturnal metal-detectorists. The area has been targetted based not only on Bede’s evidence, but also the 19th century find of an Anglian urn burial at Haw Hill, and the results of a fieldwalking survey conducted in 1982 prior to the erection of a new barn. The Woodbridge-based Sutton Hoo Society pledged financial support for a new survey of the area of the estate and extensive fieldwork was begun in October 2008. While this work was in progress, the site was attackd on several occasions. Sir Michael Bunbury was able to provide information to the local police which resulted in the arrest of five men – one local and four from outside the county.
Part of the importance of the Rendlesham site is in its association with King Rædwald, the East Anglian Bretwalda or overlord of all southern Britain, who is still the best candidate for the burial in Mound 1 at Suton Hoo. Bede relates the story of Rædwald’s conversion to Christianity and how he erected an altar to Christ in his existing temple to the heathen gods: as a polytheist, the king would have seen no conflict in this, but the monotheist Bede heartily disapproved. Rendlesham therefore has the potential to offer a great deal of information about the conversion of the English from the old religion to the new – with all the implications for social and economic change which this entailed.
Because Rendlesham is so important, it is to be hoped that whoever is convicted of the crime of looting the site is dealt with harshly as an example to others. Failure to offer a meaningful deterrent in this high-profile case will be construed as encouragement by the looters.

The Sutton Hoo Society can be found here

The Staffordshire Hoard

October 14, 2009

The discovery of a hoard of gold and silver in a field near Lichfield in September 2009 made headlines all around the world. Some reportage took the view that the find would re-write English history by showing that the country was rather wealthy in the Early Anglo-Saxon period (circa 400-650 AD). Other journalists expressed the finder’s surprise and joy at making a metal-detecting find which would surpass all others in monetary value.
One point which was generally overlooked in all the media interest in the finder’s personal circumstances (middle-aged and unemployed, using his detecting as a form of exercise and a hobby) and the likely sum he will receive as a reward (‘seven figures’ as Dr. Kevin Leahy, the PAS officer, put it) is that the hoard represents military fittings – not whole swords and shields as might be expected from a battle site, but just the gold and silver fittings from them. This must suggest that the pieces were removed deliberately – and often with some force – from weapons and collected for disposal.
The decorated objects all bear Style II decoration which puts them in the date-range 550-650 AD in England. Lichfield was a major centre of Mercian power in the 7th century and a menace to its neighbours and rivals – East Anglia, Northumbria, Wessex and the tiny Welsh kingdoms to the west. The hoard does not tell us much about weapons and warfare in the 7th century – but it does shed some light on the relationships among the Anglo-Saxon kingdoms and their neighbours on the Continent and in Scandinavia.
Until the discoveries at Sutton Hoo in 1939, the general view was that the Anglo-Saxons were an impoverished and unimpressive people. That view could no longer be maintained with the unearthing of the royal treasure ship, but it was still possible to argue that the king’s barrow was exceptional and his wealth was derived from family links with Sweden. The new hoard demonstrates clearly that the material recovered from Sutton Hoo was not exceptional in 7th century England, and may not have been the finest workmanship around at that time. A re-evaluation of the wealth and craftsmanship of the Anglo-Saxons generally – not just the Sutton Hoo and Prittlewell finds – will have to be undertaken once the hoard is published.