Ask first, post later
Start with a question, not a parcel. Send a photo on WhatsApp or call, and you will get a straight answer on what testing tier suits your item and what the report will cover. None of it commits you to posting anything.
This is a UK-wide postal testing service. There is no shop to visit and no counter. Wherever you live, the process is the same: ask first, then decide.
What makes "the difference" page different from the trade pages
The trade sub-pages (pawnbrokers, charity shops, solicitors, auction houses) each argue the independence case for one audience. This page argues it once in general terms: that an XRF test produced by a party that is also buying has the structural conflict a probate solicitor, HMRC or an executor is entitled to question, whereas a test from a party with no interest in the outcome does not. The trade pages reference back to this one rather than restate it.
A hallmark
A UK hallmark is a set of legally-controlled marks applied to a precious metal item by one of the four UK Assay Offices: London (Goldsmiths'), Birmingham, Sheffield or Edinburgh. The Hallmarking Act 1973 reserves these marks. Anyone in trade selling a precious-metal item above the minimum weight without one commits an offence under the Act.
The mark guarantees that the item meets a legal minimum standard of purity (e.g. 375 ppt for 9ct gold). It does not say what the actual content is; the actual content could be 375 ppt or it could be 390 ppt, the mark is a floor, not a measurement.
A hallmark is also a record. It identifies the Assay Office that tested the item, the year it was marked, and (where present) the maker / sponsor. Antique hallmarks are themselves valuable historical records.
An acid test
A traditional acid test involves filing a small mark into the item to reveal the metal underneath, then applying a testing acid of a set strength to that mark and observing the reaction. The reaction colour and rate indicate the carat range of the gold. Cheaper and faster than XRF, used widely in pawnshops, jewellers and gold-buying counters before XRF became affordable.
It has three limits. It is destructive (the filed mark is permanent), it is operator-dependent (the result varies with technique and acid age), and it is an approximation (it puts the item into a carat range, not a parts-per-thousand reading).
On most modern Niton-equipped buyers, acid tests are kept for special cases, heavily plated suspects where XRF is being defeated by plating thickness, rather than as the primary method.
An XRF test
XRF spectrometry is non-destructive, fast, and measures detectable elements at the points tested. Results depend on the instrument and measurement conditions. Unlike a hallmark, a surface XRF reading does not guarantee the composition throughout an item.
It does have limits worth knowing. It reads only the surface and a short depth into the metal, so heavy plating can occasionally mimic solid metal on a single scan. The SOP defence is a multi-point scan trace (readings at face, edge and corners) which exposes plating signatures cleanly.
It also does not read inside a closed bezel-set stone, and it does not read non-metallic materials. For stones, the in-house gem service is the right tool.
This page compares the three methods so you can choose the evidence you need. If you are selling to GoldPaid rather than paying for a test, every item you post for a valuation is XRF-tested as part of the free service, and XRF testing explained sets out how that works and what it means for your offer.
When each method is right
| Question | Hallmark | Acid test | XRF |
|---|---|---|---|
| Does this meet a legal standard? | Yes, that is what it does. | Roughly. | Yes, and shows by how much. |
| What is the actual fine gold content? | No, guarantees a floor only. | No, gives a carat range. | Yes, to parts per thousand. |
| Is this plated or solid? | The hallmark may indicate, if present and trusted. | Yes, after the filing. | Yes, with multi-point scan. |
| Will my item be marked or damaged? | No, applied by the Assay Office. | Yes, small filed area. | No, non-destructive. |
| What other metals are in the alloy? | No. | No. | Detectable elements at the tested points. |
| Is it valid in court / probate / insurance? | Yes, legal mark. | Not on its own. | As a written composition record, yes; it does not replace a formal probate or reinstatement valuation, and court admissibility depends on the proceeding. |
Cover and tracking
Your parcel travels on Royal Mail Special Delivery, and Royal Mail cover may be available up to £2,500 depending on the postal method and cover level used, and if a parcel may be worth more than that we split it across more than one prepaid label at no charge, each with its own tracking number and cover.
The label is Royal Mail Special Delivery Guaranteed by 1pm next working day, with full tracking and signature on receipt. The tracking link is emailed to you the moment the label is issued.
What you get back, and when
Your item is returned by Royal Mail Special Delivery on the same working day the report is issued. Return postage and its cover are included in the testing fee. There is no separate return charge.
If, for any reason, an item cannot be tested (badly damaged surface, non-metallic core, equipment misalignment), we tell you straight, refund the testing fee, and return the item the same day.
The testing pledge
You can use this testing service with no intention of selling. Nobody here is paid more for turning a test into a sale. The report carries no offer and no upsell, because it is not the front end of anything. We test. What you do next is your own business.
Ask at the end whether the item is something we would buy and you will get an honest answer. Do not ask, and nothing follows.
What this report is, and what it is not
The report identifies the elemental composition of an item to the accuracy of the analyser. The composition report does not replace a UK hallmark, an Assay Office fire assay, or an insurance reinstatement valuation. Any separately ordered replacement-value assessment is a different document: check your insurer’s valuer and report requirements before ordering. We say so in plain English on the front page of every report.
If a report leaves any doubt, we will tell you what the next step would be, typically a UK Assay Office fire assay (destructive but definitive) for high-value disputes, or a written insurance valuation from a qualified independent valuer for reinstatement cover.
Why sell to GoldPaid
GoldPaid is a small, owner-run UK business built on one promise: show the working. Every item is weighed and XRF-assayed, and every offer is itemised in writing. Postage is free and tracked both ways, and there is never a countdown or a hard sell. If something is worth more to a specialist than to us, we say so.
Common questions
Is an acid test enough to know whether to sell my piece?
Acid testing may require a filed mark and needs experienced interpretation. Our plating check at £25 examines the item non-destructively and provides a written assessment. Thick plating or a concealed core can leave the result inconclusive; the report will say when solid metal cannot be confirmed.
Can XRF and a hallmark disagree?
Yes. A difference needs investigation rather than an assumption that either result is correct. Repairs, solder, replaced components, surface plating and measurement conditions can affect an XRF reading. We compare readings at several points with the hallmark and construction, and state when further testing is needed.
Is fire assay better than XRF?
The methods answer different questions. Fire assay is a laboratory method for determining gold content in a sample and consumes the sample. XRF provides a non-destructive reading at the tested surface points, with limitations for plated or mixed-construction items. For a disputed result, ask an Assay Office which sampling and analytical method is appropriate; a test result alone does not guarantee acceptance in legal proceedings.
Why do you not offer acid testing?
Our paid report is designed as a non-destructive assessment. Acid testing can require filing or scratching. If surface readings cannot resolve an item, we explain that limitation and discuss appropriate further testing.
Not the question you had? The full GoldPaid FAQ covers the rest, from postal cover and ID checks to what happens if you decline the offer.