Black Range Amethyst

Amethyst in Southwest New Mexico

- ROBERT BEARD

An accessible amethyst collecting locality is in the northern Black Range in southern Catron County, New Mexico approximately a half mile north of the border with Sierra County. The locality is a former mining prospect on a hilltop. Amethyst is found within a trench and adjacent rocks excavated from the trench. The locality is within Gila National Forest, and it is easily reached by parking along NM-59 and a short hike.

AMETHYST

Amethyst is the purple variety of quartz. Deep violet and dark purple are among the most prized varieties. It has been known as gemstone since ancient times. Pliny the Elder, the Roman Naturalist from the First Century, described the color of amethyst being near to wine, but not quite that of wine. The name is said to be from the Greek word "Amethustos," which translates to “not drunken." Amethyst was said to have the power to prevent drunkenness.
Amethyst hues range from deep purple to bluish violet to light pink.
The chemical formula is silica dioxide, or SiO2, and purple is from trace amounts of iron or other impurities in the crystal lattice. Radioactivity can also affect the color of amethyst. Buyers should be aware of the potential for artificial enhancements to amethyst.

Hydrothermal veins in volcanic rocks can have amethyst under the right conditions. Silica and other metals often enrich the hydrothermal fluids. As the fluids cool, the silica comes out of solution and crystallizes. Veins often have gases under extreme pressure during formation, and crystals can grow in the spaces occupied by gases. Under the right conditions, amethyst can form during crystallization. Some veins have trace amethyst, while others have abundant amethyst.