This is a solid gold chain. Great for pendants or charms! Weight can vary +- 5% as these are handmade chains! Millimeter thickness is exact to 0.01mm measured by laser.2.6mm - 5.7g (0.24g per inch). 3.6mm - 8.8g (0.37g per inch). 4.7mm - 14.8g (0.62g per inch). 5.7mm - 21.1g (0.88g per inch). Has a nice weight to it! Let us know if you have any questions!