Why fake gold exists
Most "fake" gold on the second-hand market is not a scam item. It is plated, filled, rolled or stamped jewellery that was always sold as such but has drifted from its paperwork over decades. The point of an at-home check is to flag those items before they are mistaken for solid gold; the point of an XRF assay is to settle them definitively when they reach us.
Test 1, The magnet test
Pure gold is not magnetic. If a piece is attracted to a strong neodymium magnet, it contains a magnetic base metal (typically iron, nickel or steel) and is not solid gold. The reverse is not proof: many plated, filled or low-carat alloys are also non-magnetic. A magnet is a fast fail-test, not a pass-test.
Test 2, Density (the bench-jeweller’s test)
Gold is very dense. Pure 24ct weighs about 19.3 g/cm³. 18ct weighs about 15.5 g/cm³, 9ct about 11.3 g/cm³. If you can measure the item’s weight and the volume of water it displaces, the density tells you a lot. The catch is hollow items, stone settings and solder, all of which throw the figure off. A bench jeweller will isolate the metal first; at home, this is a rough sanity check, not a verdict.
Test 3, The ceramic plate scratch
A piece of real gold leaves a gold-coloured streak on an unglazed ceramic tile. A piece of brass or plated metal usually leaves a darker, blacker streak. This test does mark your item, so use the inside of a clasp or somewhere out of sight. It is also a rough check, not proof, and not advisable on anything sentimental.
Test 4, Read the hallmark properly
A UK hallmark is the easiest test most people miss. 375 = 9ct, 585 = 14ct, 750 = 18ct, 916 = 22ct, 999 = 24ct. A standing lion is a sterling-silver mark, not a gold mark, so a "lion" on a yellow piece usually means the yellow is gold-coloured plate over silver. Marks like GP, GF, RG, HGE and 1/20 identify plated, filled or rolled-gold items rather than solid gold.
Counterfeit marks exist but are rarer than people assume; a UK assay-office punch struck into the metal is hard to fake convincingly. See the gold hallmark guide for the symbol set.
Test 5, The acid test (and why we do not use it)
The traditional jeweller’s acid test scratches the metal onto a touchstone and applies an acid graded for a carat (e.g. 9ct, 18ct, 22ct). If the streak dissolves under a higher-carat acid, the item is below that carat. It is informative, and it permanently marks your piece. We replaced acid testing with XRF for this reason: XRF measures the same composition without leaving a trace, so if you decline our offer your items go back to you exactly as they came in.
When in doubt, ask before posting
If a clear photo of the mark, the back of the clasp and the inside of a ring is sent on WhatsApp, an experienced eye can usually tell whether a piece is worth posting in. There is no charge for that conversation and no obligation to send anything afterwards.
Common questions
Is gold-plated jewellery worth selling?
In most cases the gold layer is too thin to be recovered economically. We will tell you honestly when a piece is plated rather than solid.
Does a magnet test prove gold is real?
No. It only proves the piece is not iron, nickel or steel. Many fakes pass the magnet test; an XRF assay is the only conclusive answer.
Can a UK hallmark be faked?
It can, but a struck UK assay-office punch is hard to fake well. Most "fake" gold is actually plated or filled and is honestly marked as such, GP, GF, RG or 1/20.
Will the acid test damage my piece?
Yes. It marks the item permanently. We use XRF instead, so nothing is scratched, filed or acid-tested.