Quartz Crystal Interior — Amethyst Cave
71.20 £
The interior face of an amethyst geode photographed at 2:1 macro scale — the purple quartz crystals with their hexagonal cross-sections and growth surface features fully resolved.
Description
Amethyst quartz owes its purple colour to irradiation-induced colour centres associated with iron impurity substitution in the crystal lattice — a colour mechanism that explains both the crystal’s photosensitivity (UV exposure fades the colour) and the characteristic uneven colour distribution associated with growth-zone differences in iron concentration. This photograph, made at 2:1 reproduction from within a Brazilian amethyst geode cavity, captures the crystal faces with sufficient magnification to resolve growth hillocks, dissolution pits, and the precise hexagonal cross-section geometry of the prism faces, while the internal colour distribution within individual crystals reveals the growth history of the crystal face in successive zones of differing iron content.
