Price used: pure gold around €120/g on 8 June 2026. The price moves every day — check it at the date you're reading.
When I spot a second-hand piece I like, I don't look at the tag first. I do a little mental calculation, the same one as comparing two bags of rice by the price per kilo. In thirty seconds, I know whether the price is fair or whether I'm being taken for a tourist. Here's exactly how I do it — you can do it yourself.
You only need three pieces of information
- The weight of the piece (in grams) — often given, otherwise ask for it.
- The fineness — for 18-carat, 75% pure gold. (The hallmark confirms it for you.)
- The day's pure-gold price — around €120/g in early June 2026.
With that, you calculate the value of the gold actually contained:
weight × fineness × spot = metal value
Concrete example: an 18-carat chain of 6 grams. 6 × 0.75 × 120 = €540 of pure-gold value.
That's your reference point. The asking price, you always compare to that number — not to what "it would cost new".
What markup is reasonable?
Nobody sells gold at its exact metal value — there's always a markup (the shop lives on it, and a fine piece is worth more than its weight). The real question is: how much above the metal value?
| Asking price vs metal value | Reading |
|---|---|
| Close to metal value | Excellent deal (rare) |
| +15 to +40% | Fair for second-hand |
| +50 to +80% | Acceptable if a fine / vintage piece |
| × 2 or more | That's new-piece pricing, forget it for investment |
On our chain with €540 of metal: up to ~€700-750, it's honest second-hand. At €1,100, you're paying a new markup on a second-hand piece — barring an owned-up crush, it's no longer investment. And if it's a summer-sale promo tempting you rather than second-hand, keep in mind the discount never bites into the metal, only into that markup — I explain why here.
The two classic traps
- The fineness you assume. If you take "18-carat" at face value with no hallmark, your whole calculation is wrong. Check the hallmark first. And beware of 9-carat sold "cheaper": its price per gram of real gold is often worse — that's the whole subject of this article.
- The stones. On a set piece, the stated weight includes the stones, which aren't gold. For investment, I prefer stone-free, simpler to value. For a fine piece with a stone, I accept the markup — but I know I'm then paying for the pleasure, not the metal.
It's exactly this calculation I run automatically on OrOGramme: for each piece, the price divided by the weight, normalised. And since I only reference 18-carat and above, you can compare pieces directly without redoing the maths each time.
Eleven French second-hand 18-carat gold shops, normalised per gram and sorted by the best deal on the metal.
To wrap up
You don't need to be an expert to know whether a price is fair: three figures, one multiplication, and you know. Weight × fineness × spot gives you the real value; the rest is markup to judge depending on whether you're buying for pleasure or for investment.
I'm telling you the method I use for myself. Make your own choices — but keep the reflex: price per gram before the tag.
Sources / to go further:
- Pure gold price ~€120/g on 8 June 2026: veracash.com, accessed 8 June 2026
- Check the fineness with the hallmark: OrOGramme article
- Why the markup climbs (and how to read it): OrOGramme article