Short answer
A fake Cartier tumbaga bracelet is a replica. The metal is a gold and copper alloy. Sellers use the word tumbaga to suggest the piece is old or made from pre-Columbian gold. Cartier does not make a bracelet called the Tumbaga. No Cartier catalog lists that name. A bracelet with that label comes from a replica maker or a reseller.
What tumbaga is
Tumbaga is an alloy of gold and copper. Metalsmiths in Mesoamerica and northern South America used it from about 500 CE to the 1500s. Common mixes run from 60 percent gold to 80 percent gold, with copper making up the rest. Some pieces also contain trace silver. The alloy is harder than pure gold. That hardness let smiths cast and hammer shapes pure gold cannot hold. Museums hold tumbaga objects from the Quimbaya and Muisca cultures.
Why sellers use the word
The term carries weight. It suggests an antique. It also explains a metal color between yellow gold and rose gold. A copper-rich alloy looks warmer than 18k gold and duller than 24k gold. Buyers who see that color and hear "tumbaga" may accept it. Test results show brass, bronze, or gold-plated copper in most cases.
Marks on a real Cartier bracelet
Cartier stamps each gold bracelet with a set of marks. Check these points.
- Purity mark. French pieces carry the eagle head for 18k gold. Other markets use "750" or "Au750".
- Maker mark. A diamond-shaped stamp with the Cartier name and a symbol.
- Serial number. Engraved, not stamped, and matched to the model.
- Model name. The Love bracelet and the Juste un Clou carry their own engraving.
A tumbaga piece lacks the eagle head. It may show "18K" applied by hand. Hand stamps sit uneven, and the depth changes across the surface.
Tests
Magnet test. Gold and copper are not magnetic. A strong pull means a steel core.
Acid test. A jeweler applies nitric acid to a scratch. Copper reacts. Gold does not.
X-ray fluorescence. A handheld XRF unit reads the metal mix in seconds. It reports gold, copper, zinc, and nickel percentages. This is the only test that returns a number.
Weight. A size 17 Cartier Love bracelet in 18k gold weighs about 30 to 38 grams. A copper copy of the same size weighs less, near 25 to 30 grams, because copper is less dense than gold.
Price signals
An 18k Cartier Love bracelet sells new for about $7,000. Used pieces trade between $4,500 and $6,500. A tumbaga or brass copy sells for $20 to $200. Any offer below $1,000 for a piece described as solid 18k gold does not match the metal value.
What is unknown
Cartier publishes no data on tumbaga. No archive connects the company to the alloy. Treat the term as a sales word, not a product line.