

Royal Mint · United Kingdom
Half-ounce fractional Britannia gold bullion coin. Same iconic Britannia reverse design and 99.99% purity as the 1 oz version.
| Mass | 15.552 g |
| Troy Ounces | 0.5 oz |
| Diameter | 27 mm |
| Thickness | 2.08 mm |
| Edge | reeded |
| Purity | 99.99% Gold |
| Fineness | 0.9999 |
| Density | 19.3 g/cm³ |
| Face Value | 50 GBP |
| Series | Britannia |
| First Minted | 1987 |
| Ping Frequency | 4,769 Hz |
Use these values to verify an authentic Gold Britannia 1/2 oz. All tests can be performed with a digital scale, calipers, and the EON ping tester.
Use a 0.01g digital scale. Calibrate first with a known object (a €2 coin = 8.50g).
Use plastic calipers (not steel — avoid scratching). Or use the camera tool with a bank card as reference (ISO 7810: 85.60mm × 53.98mm).
Balance the coin on your fingertip and tap the edge with a pencil or plastic pen. Use the Ping Tester to analyse the ring.