The Complete Beryl Guide

Red: Bixbite, only found in one location in Wah Wah Mountains, Utah,USA
Bright yellow: Heliodor. If yellow becomes deep toward orange: “golden Beryl”
Colorless: Goshenite
Deep blue: only found on one location in Brazil: will quickly loose its color if exposed to daylight
Green: too light to be considered emeralds. Problematic as a green beryl is much cheaper than an emerald but sometimes still sold as one

Considering the range of beryls clarity can vary from eye-clean to very included.

Beryls are generally quite hardy unless they are strongly included.
Red beryls tend to be more like emerald in this respect and may be fragile if the gem has many surface reaching fissures. A dampened, non-abrasive cloth is best used to clean beryl jewelry.

Color: Heating can take out a secondary color rendering a deeper, more saturated color
Color: Sometimes colorless beryls are irradiated to produce yellow colours. This colour is considered stable. Maxixe beryl is almost always irradiated is often irradiated in a laboratory. Color is not stable. Some colourless and light pink beryl from Minas Gerais is irradiated to produce maxixe beryl
Clarity: colourless oil and resins are sometimes used to hide fissures in red beryl

Beryls may be cut several different ways, though emerald cut and oval cut gems tend to predominate.

Large beryls with high level of saturation
Rare beryls such as Red beryl
Special effects such as “cat’s eye”
Borderline beryls: “is it an emerald or is it a green beryl”