Amethyst — specimen 0344, photo © NMNHS
Uruguay, Artigas Department
Weight: 0.44 ct; size: 5.44 | 4.17 | 3.36 mm; shape: oval; colour: medium violetish blue; very slightly greyish; clarity: eye clean; cut: excellent; treatment: none.
Very clean specimen; design ‘Merle’s Cut’ by Merle Reinikka, excellent cut by Tan Pen.
More information from ‘Classification’
A violet variety of quartz. The colour is caused by iron impurities in the 10s to 100s parts per million range.