Spirographic-cut Ametrine by Dalan Hargrave

Spirographic-cut Ametrine by Dalan Hargrave
Ametrine, sometimes also known in the trade as bolivianite, is a naturally occurring variety of quartz—a mixture of amethyst and citrine with zones of purple and yellow or orange. Almost all commercially available ametrine is mined in Bolivia. The color of the zones visible within ametrine are due to differing oxidation states of iron within the crystal—a result of there being a temperature gradient across the crystal during its formation. The present stone possesses completely natural, unenhanced colors. Cut along the c-axis of the original crystal, this is a cross-section showing the pattern of colors unique to the Anahi Mine—alternating violet amethyst and orangey-yellow citrine. This lovely stone, produced by lapidary artist Dalan Hargrave, with its scalloped edges and a bright purple hue and three zones of citrine, exhibits a complicated faceting style which incorporates flat and concave faceting as well as a double-spirographic cut. Adopting a design utilized by the glass industry for cutting leaded glass, known as the "American brilliant" pattern, he coined the term "spirographic-cut" referring to the intricate incisive patterns on the bottom of the gemstone. The flat polished top allows for the viewing of the pattern below. No other lapidaries have produced similar work or executed exactly this pattern of geometric shapes. Weighing approximately 95.0 carats and measuring 32.0 x 12.2mm