Weigh the same gold chain three times and you can get three completely different numbers — 30, 19.3 or 0.96 — without the chain changing at all. They are grams, pennyweight and troy ounces, and the only thing that changes is the unit. Knowing which one you are being quoted in is the difference between comparing two offers and guessing at them.
Three units, one piece of gold
The gram is the unit most people already own a scale for, and the one this site uses everywhere — in the estimator, in the per-gram table and in every written offer.
The pennyweight (abbreviated dwt, from the old Latin denarius) is a jewelry-trade unit that never went away in the United States. One pennyweight is 1.5552 grams, and twenty of them make a troy ounce. If a buyer quotes you a price “per dwt”, this is what they mean.
The troy ounce is how the metal itself is priced on the market: when you read that gold is at some number per ounce, that ounce is a troy ounce of pure gold — 31.1035 grams. It is not the ounce on your kitchen scale. The everyday (avoirdupois) ounce is 28.3495 grams, so a troy ounce is roughly 10% heavier. Mixing the two up is the single most common arithmetic mistake people make before they sell.
| Unit | In grams | In pennyweight | In troy ounces |
|---|---|---|---|
| 1 gram | 1 | 0.6430 dwt | 0.03215 ozt |
| 1 pennyweight (dwt) | 1.5552 | 1 | 0.05 ozt |
| 1 troy ounce (ozt) | 31.1035 | 20 | 1 |
| 1 ordinary ounce (oz) | 28.3495 | 18.229 dwt | 0.9115 ozt |
Fixed conversions — they do not move with the market. Only the price per unit does.
Why the unit changes how a price looks
A pennyweight is about one and a half grams. So a price quoted per pennyweight is roughly 1.55 times larger than the same price quoted per gram — for exactly the same gold, at exactly the same rate. Neither unit is dishonest. What causes damage is comparing one against the other as though they were the same number.
So a shop paying “$62 a pennyweight” and a shop paying “$40 a gram” are paying almost exactly the same thing. Put both quotes in one unit before you decide anything — and if a price is quoted without naming its unit, that is the first question to ask, not the last.
Our offers are written in grams, with the weight, the karat and the pure gold content all shown, so there is no unit to decode. The estimator on the homepage works in grams for the same reason.
From weight on a scale to gold you get paid for
Weight alone never decides the metal value, because almost nothing is pure gold. What the scale reads is gross weight — everything on it. What gets paid for is the pure gold content inside that weight.
| Karat | Usual stamp | Pure gold | Pure gold in 10 g |
|---|---|---|---|
| 24k | 999 / 9999 | 99.9% | 9.99 g |
| 22k | 916 | 91.6% | 9.16 g |
| 18k | 750 | 75.0% | 7.50 g |
| 14k | 585 | 58.5% | 5.85 g |
| 10k | 417 / 416 | 41.7% | 4.17 g |
| 9k | 375 | 37.5% | 3.75 g |
Karat divided by 24 gives the strict ratio — 14 ÷ 24 is 0.5833 — while the stamp on the piece reads 585. The half-percent gap is the alloy standard, not an error, and it is far too small to matter next to getting the unit or the karat wrong.
A worked example, in both units. A 14k chain that weighs 30 grams is 19.3 pennyweight, or 0.96 of a troy ounce. At 58.5% purity it holds about 17.6 grams of pure gold — and that pure content, priced at the day’s live spot, is the metal value. Everything else about the chain — who made it, whether it is signed, what condition it is in — sits on top of that number, never underneath it.
What is on the scale that is not gold
This is where home estimates usually go wrong. All of the following add weight without adding gold:
Stones
Diamonds and coloured stones weigh something and are valued separately, on their own merits. They are not part of the metal weight.
Clasps and springs
Spring rings, lobster clasps and pin mechanisms often contain steel. Small, but real on a light chain.
Watch movements
A gold watch case is gold; the movement, crystal and often the buckle are not. Watches are rarely valued on metal anyway.
Weighted silver
Candlesticks and some hollow handles are filled with pitch or plaster for stability. The filler weighs more than the silver around it.
Plated pieces
Gold-filled and plated items are mostly base metal. They are assessed case by case, not weighed as gold. Which one is it?
Mixed karats
10k, 14k and 18k are not worth the same per gram. Weigh them in separate groups or the average tells you nothing.
Weighing it yourself, sensibly
- 1Use a digital scale that reads gramsOne decimal place is enough for a chain; a jeweler’s scale reads to a hundredth of a gram. Set it to grams, not ounces — a kitchen scale’s “oz” is the wrong ounce.
- 2Sort by karat firstGroup 10k with 10k, 14k with 14k, and weigh each group on its own. One mixed number cannot be converted back into anything useful.
- 3Weigh the piece, nothing elseNo box, no cord, no pouch. If a piece has obvious non-gold parts, note them rather than trying to subtract a guess.
- 4Apply the purity, then stopWeight times purity gives pure gold content — the floor. It is a sanity check, not a valuation, and it says nothing at all about a maker’s mark or a stone.
Do not scratch, file or acid-test a piece to find its karat.
Every one of those leaves a mark, and on a signed or antique piece a mark is money. There is no need for it either: we weigh each piece and confirm its karat by testing on the bench, at no cost and with nothing to undo. The same goes for polishing — a buffed hallmark is a hallmark you can no longer read.
Not sure what you are looking at, or what unit you have been quoted? Send a photo of the piece and the stamp.
Ask on WhatsAppHow the weight is handled here
Each piece is weighed and its karat confirmed by testing before anything is valued, and the pure gold content is priced at the day’s live spot price. 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 from the scale and which part did not.
Plain, unmarked 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 the scale alone would suggest — and nothing is melted, altered, dismantled or sold until you accept in writing. If a piece is worth more whole than it is worth as metal, that is what the written offer will say.
Frequently asked questions
How many grams are in a pennyweight?
One pennyweight (dwt) is 1.5552 grams, and there are 20 pennyweight in one troy ounce. It is an old jewelry-trade unit that is still used every day in the United States — which is why the same gold can be quoted as a price per gram or a price per pennyweight.
Is a troy ounce the same as a normal ounce?
No. A troy ounce is 31.1035 grams; the ordinary (avoirdupois) ounce used for food and post is 28.3495 grams. A troy ounce is about 10% heavier. Gold, silver and platinum are always quoted in troy ounces, so a kitchen scale set to ounces will not give you a figure you can use.
Why do some gold buyers quote a price per pennyweight?
Because a pennyweight is a larger unit than a gram, a price per pennyweight is a bigger-looking number for the same money — and a price per gram is a smaller-looking number for the same money. Neither is dishonest on its own. The problem is comparing one against the other without converting. Multiply a per-gram price by 1.5552 and you have the equivalent per-pennyweight price.
How do I weigh my gold jewelry at home?
Use a digital scale that reads in grams to at least one decimal place. Weigh pieces of different karats separately, since 14k and 18k are not worth the same per gram, and leave out anything that is not part of the piece. Treat the result as an estimate: home scales drift, and stones and clasps sit on the scale without being gold.
Does the weight of the stones count as gold?
No. What the scale shows is gross weight — everything, including diamonds, coloured stones, steel spring clasps and watch movements. Metal value is calculated on the gold weight only, and stones are valued separately on their own merits. A stone-set ring can be worth far more than its metal, but not because the stones weigh something.
Do I need to know the weight before I send my gold in?
No. Knowing it helps you sanity-check an estimate before you post anything, but nothing depends on your figure. Every piece is weighed on our scale and its karat confirmed by testing, and the metal value and any premium are shown to you separately in writing before you decide anything.