Category: Gem Notes

Quartz

This issue, the tables turn to look at a mineral family prevalent in the industry—it’s available in a wide range of colors and from a wide range of localities.

Cassiterite

It’s a common mineral, found on every continent, but faceting rough is rare—unfortunate, since its lighter versions can display dispersion almost twice that of diamond.

Pezzottaite

Named after Dr. Federico Pezzotta from the Natural History Museum of Milan for his work on Madagascar’s granitic pegmatites, this rare mineral species is relatively new.

Hauyne

There has never been commercial production of this rare member of the sodalite group, celebrated for its striking blue color.

Jeremejevite

Introduction: Jeremejevite is not well known among the general public and it is safe to say, it is not a common gem seen or familiar within the gem and jewelry industry. Unlike many gems within the…

Wulfenite

INTRODUCTION Wulfenite is a mineral species crystallizing in the tetragonal system, lead molybdate, with the formula PbMoO4. It was named after the Austrian mineralogist, Franz Xavier Wulfen. Wulfenite is almost always found as thin, tabular crystals…

Kyanite

Kyanite can be extremely attractive as mineral specimens (Figure 1) and is actively sought after by collectors.

Aragonite & Calcite

Just as graphite and diamond have the same chemical composition but crystallize in two different systems, so is the case with aragonite and calcite

Zincite

To complicate matters, zincite can be and has been intentionally synthesized in a laboratory. Many years ago, synthetic zincite was used as semi-conductor crystal detectors in radios before the advent of vacuum tubes.