A silver-topped 18 karat (18K) yellow gold bar brooch set with three button-shape natural white pearls interspaced by 20 rose-cut and two old-cut diamonds. Unmarked but tested as 18 karat gold. Dimensions: 5cm long x 0.4 x 1 cm Weight: 3.25 grams 

(Chain not included)

Because of different gold testing practices, (traditional acid and stone test vs. eBay's Authenticity Guarantee electronic XRF digital gold testing machine), items stamped 14k may read or actually be between 13.5k-15k gold.  Until 1981, manufacturers of jewelry could use gold that was 13.5 karat or higher and round off, thus still stamping it 14k.  Much of the jewelry sold on eBay is older than 1981.

In the same way, French 18 karat jewellery stamped with the eagle’s head guarantee mark or the owl import mark for 18 karat gold may actually be between 17.35k-19k.

Where relevant, items have been tested for purity using the KEE Electronic Gold Tester, and have been listed according to the results gained from this analogue tool.