Glass part: Approx. Φ 9 mm
Pierce bracket: K14 gf (catch is resin)
<What is K14gf ...>
It is a gold layer crimped to a material (brass) with high heat and pressure, and when the weight of the gold layer is 1/20 or more of the total weight including the material, it is called <gf> gold filed (gold tension).
Because it is made of a much thicker layer than gold plating, there is little to be peeled off even if it is used for a long time.
Also different from plating, there is a sense of luxury in the color of the gold.