Beryl

Beryl

Formula: $\text{Be}_3\text{Al}_2(\text{Si}_6\text{O}_{18})$

Physical Properties:

• Color: Colorless, green, blue, yellow, white, pink, etc.


• Luster: Vitreous, sub-vitreous, waxy, greasy.


• Hardness: 7.5 – 8 (Mohs scale)


• Specific Gravity: 2.63 – 2.92


• Crystal System: Hexagonal


• Classification: Beryl Group $\rightarrow$ Beryl Supergroup

Gemological Varieties:

• Emerald: Green beryl.


• Aquamarine: Blue beryl.

Etymology & Historical Notes:

The name is likely derived from the Greek word beryllos, which historically referred to various blue-green stones. In mineralogical studies, beryl can occasionally be misidentified with Apatite.

Notable Records & Research:

• Giant Crystals: A reported beryl crystal measuring 18 m in length and 3.5 m in width was allegedly recovered from Malakaina, Madagascar; however, this claim remains scientifically unverified and is subject to skepticism.


• Microstructure: Microporous beryl (and cordierite) may contain molecular nitrogen ($\text{N}_2$) within its structure (Bebout et al., 2006).


• Structural Relationships: Cordierite (and particularly its high-temperature polymorph, Indialite) exhibits structural similarities to beryl. As of April 2023, new discoveries of Beryllocordierite-Na and Beryllosachanskinite-Na suggest a potential integration of these two mineral “families.”