Amethyst — specimen 0121, photo © NMNHS
Weight: 6.93 ct; size: 14.41 | 12.01 | 6.98 mm; shape: oval; colour: light bluish violet; very slightly greyish; clarity: eye clean; cut: fair; treatment: none.
Very clean specimen; mixed style cut with large window.
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.