Three chains can sit side by side on a table, the same colour, the same weight, the same shine — and one of them is worth hundreds of times what the other two are. The difference is not something you can see. It is stamped on a tiny tag next to the clasp, in letters most people have never had a reason to read.
Three different things wearing the same colour
Solid gold is gold alloy all the way through. Cut it in half and the cut face is the same metal as the surface. The karat — 10k, 14k, 18k, 22k — tells you how much of that alloy is pure gold, and the whole weight of the piece counts towards its metal value.
Gold-filled is a genuine layer of karat gold mechanically bonded to a base-metal core, usually brass. It is a real, durable layer, thick enough to last decades of wear — but it is a layer. In US-marked gold-filled the layer is a stated fraction of the total weight, most often one twentieth. The core underneath is not precious.
Gold-plated is a microscopically thin coat of gold deposited electrically onto base metal. It is measured in millionths of an inch, not in fractions of the weight. It is a finish, in the same way paint is a finish.
And there is a fourth, which trips up more sellers than the other three combined: vermeil is gold over sterling silver. It looks gold and it is marked for the silver, so it usually gets sorted into the wrong pile.
| What it is | Marks you will see | Gold in it | How it is valued |
|---|---|---|---|
| Solid gold | 10K · 14K · 18K · 22K · 417 · 585 · 750 · 916 | All the way through, at the stamped karat | Weighed, karat confirmed, priced on pure gold content at live spot |
| Gold-filled | GF · 1/20 12K GF · 1/10 14K GF · G.F. | A bonded karat layer, a stated fraction of the weight | Assessed case by case — never weighed as solid gold |
| Rolled gold plate | RGP · R.G.P. · rolled gold | The same idea as gold-filled, but a thinner layer | Assessed case by case |
| Electroplated | GP · GEP · HGE · HGP · 18KGP · 18K HGE | A microscopic surface coat over base metal | No practical melt value |
| Vermeil | 925 · STERLING · sometimes “vermeil” | Thin gold over solid sterling silver | Valued as silver — send it with the silver |
| Costume | Usually no metal mark at all | None | Not a metal purchase |
A karat number standing alone means solid. The same number followed by letters means a layer. That one habit — reading what comes after the number — sorts most collections in about ten minutes.
Reading the mark that is already on the piece
Marks hide in four places, and almost never anywhere else.
Inside the band
Usually opposite the setting, sometimes beside a maker’s mark. On a resized ring the stamp may have been cut away with the old metal.
The tag by the clasp
A small flat plate on the last link, or stamped into the clasp itself. This is the one people miss most often, because it is the size of a grain of rice.
The back of the bail
The loop the chain runs through, read from behind. On lockets, try the inside rim.
The post or the back
Along the post, on the butterfly, or on the flat reverse of the front. Posts and backs are sometimes a different metal to the earring — that alone is not a red flag.
That single mark, decoded, is the whole difference between the three. A 12k layer sounds substantial until you notice the fraction in front of it: about five per cent of what is on the scale, with base metal making up the rest. A piece stamped simply 14K, with nothing after it, is 58.5% pure gold through its entire weight. Same colour. Not remotely the same number at the end.
Five checks you can do at home, none of them destructive
- 1Find the mark before anything elseRing band, clasp tag, back of the bail, earring post. Use your phone camera zoomed in with the light coming from the side rather than head-on — raking light makes a worn stamp readable when direct light flattens it out.
- 2Read what comes after the numberBare karat or bare fineness means solid. GF, RGP, GP, GEP or HGE means a layer over something else. A fraction in front — 1/20, 1/10 — tells you how much of the weight that layer is.
- 3Try a magnet, and be honest about what it provedGold is not magnetic. A pull means steel inside, so it is not solid gold. No pull proves nothing on its own: brass and copper ignore magnets too, and most plated chains are brass. This test only ever rules things out.
- 4Look where the piece rubsThe underside of a shank, the edge of a bangle, the back of a clasp, the inside of a hinge. A different colour breaking through — white, grey, pink, green — is base metal under a worn layer. Solid gold gets thinner with wear; it never changes colour.
- 5Photograph it instead of testing itSend a clear photo of the mark rather than trying to prove anything with a file or a bottle. Every piece that reaches the bench is weighed and its karat confirmed by testing anyway, at no cost, and a photograph costs the piece nothing.
Unmarked is not the same as fake. Stamps wear away over decades, get polished off, and get cut out when a ring is resized — and a great many older, handmade and non-US pieces were never stamped at all. It runs the other way too: a stamp is a claim, not proof. Both cases are settled the same way, by testing the metal rather than trusting the letters.
Do not scratch, file or acid-test a piece to find out what it is.
Every one of those leaves a permanent mark, and on a signed or antique piece a mark is money you cannot get back. There is no need for it: we weigh each piece and confirm its karat by testing on the bench, at no cost and with nothing to undo.
And do not polish anything first. Polishing is how a readable hallmark becomes an unreadable one. Tarnish and grime cost you nothing at all — they come off in seconds here — but a buffed-away stamp is gone for good, and on an antique the surface itself is part of the value.
What is worth putting in the box
Worth mailing: anything with a bare karat mark, anything you believe is solid even if the stamp is gone, anything signed, anything set with stones, and anything sterling — including vermeil, which is sterling underneath its gold. Broken, bent, single and unmatched pieces count: condition does not change metal value, so send them as they are.
Usually not worth mailing on its own: pieces marked GP, GEP or HGE, gold-tone costume jewelry with no metal mark at all, and anything a magnet grabs firmly. There is no practical melt value in an electroplated surface, whatever a scrap advertisement implies.
Ask first: gold-filled. We buy 10k, 14k, 18k, 22k and 24k, plus gold-filled evaluated case by case — a quantity of it is a different conversation from one bracelet, so send a photo of the marks and get a straight answer before you pack anything.
Not sure which pile something belongs in? Photograph the mark and ask. It costs nothing and it saves you posting the wrong things.
Ask on WhatsAppWhat happens to it once it is here
Every piece is weighed and its karat confirmed by testing before anything is valued — the mark is a starting point, never the answer. The pure gold content is priced at the day’s live spot price, and the offer comes to you in writing with the metal value and any brand or gemstone premium shown separately, so you can see which part of the number came off the scale and which part did not.
Plain gold is paid on its metal content. Signed, antique and gem-set pieces are valued on the resale market instead, which is usually well above what weight alone would suggest — we are jewelers, not a melt shop, and the best pieces we buy go into our own collection. Nothing is melted, altered, dismantled or sold until you accept in writing, and if you decline, the exact pieces you sent come back to you free and fully insured — plated strays included.
Frequently asked questions
Is gold-filled jewelry worth anything?
It has real gold in it, unlike plate, but far less than the karat number on the mark suggests. In gold-filled the karat layer is bonded to a base-metal core and makes up a small fraction of the total weight, so it is never weighed as solid gold. We buy 10k, 14k, 18k, 22k and 24k, plus gold-filled evaluated case by case. If you have a quantity of it, send a photo of the marks first and we will tell you honestly whether it is worth shipping.
What does 1/20 12K GF mean?
It is a gold-filled mark, and it is unusually informative. The 12K is the karat of the gold layer, and the 1/20 is the fraction of the total weight that layer represents — one twentieth, or five per cent. So the piece is about 95% base metal by weight, wearing a genuine 12k skin. Marks like 1/10 14K GF work the same way.
Does a magnet test prove my gold is real?
It can disprove it, which is not the same thing. Gold is not magnetic, so a piece a magnet pulls has steel in it and is not solid gold. A piece the magnet ignores has cleared exactly one hurdle: brass, copper and several other base metals are not magnetic either, and a plated brass chain will sit still next to a magnet all day. Use it to rule things out, then read the mark.
My ring has no stamp. Does that mean it is not gold?
No. Unmarked is not the same as fake. Marks get worn away by decades of wear, polished off, or cut away when a ring is resized, and plenty of older, handmade and non-US pieces were never stamped in the first place. It also works the other way: a stamp is only a claim, and not proof on its own. That is why every piece that reaches our bench is tested rather than taken at face value.
Is gold vermeil worth selling?
Often yes — but for the silver rather than the gold. Vermeil is sterling silver with a gold layer over it, so it is usually marked 925 or STERLING somewhere even though it looks gold. The gold layer is thin, but the sterling underneath has real metal value. Send it in with your silver rather than with your gold, and do not polish it first.
Should I mail in plated jewelry anyway, just in case?
There is no need to guess, and no need to throw anything out either. Electroplated pieces marked GP, GEP or HGE carry a microscopic layer of gold over base metal, and there is no practical melt value in them whatever a scrap advertisement implies. Photograph the marks and send them on WhatsApp before you pack anything, and we will tell you honestly what is worth shipping. If a few plated strays do travel in with a collection, they simply come back with everything else you decline — free and insured.