CLARITY SCALE IF VERY HIGH QUALITY & NO INCLUSIONS. VVS HIGH QUALITY WITH VERY SLIGHT INCLUSIONS. VVS1 HIGH QUALITY WITH SLIGHT INCLUSION. VS FINE QUALITY WITH INCLUSION SLIGHTLY VISIBLE TO THE NAKED EYE. VS1 FINE QUALITY WITH INCLUSION VISIBLE TO THE NAKED EYE. SI GOOD QUALITY WITH INCLUSIONS VISIBLE TO THE NAKED EYE. SI1 INCLUSIONS BECOMING PROMINENT TO THE EYE. I INCLUDED.
THIS GEMSTONE IS GRADED: V V S Beryl (beryllium aluminum silicate) Types/Color Aquamarine – light blue to blue-green Bixbite – Red to strawberry-red Emerald – Green Goshenite – colorless Heliodor – deep yellow Morganite – Pink to peach Other beryls may be referred to by their color, such as green beryl and yellow beryl. Mohs hardness 7.5-8 Refractive index 1.57-1.6 Critical angle 39.5° Specific gravity 2.65-2.75 Cleavage None Fracture Conchoidal, tough Dispersion Medium (.014) Heat sensitivity None Pleochroism Dichroic – Golden weak (yellow to light-yellow); Goshenite colorless, no dichroism; Green distinct (yellow-green to blue-green); Heliodor weak (gold-yellow to greenish-yellow); Morganite distinct (pale-pink to lavender-pink); Purple distinct (purple to colorless); Yellow (light yellow to medium yellow). Birefringence (double refraction) Weak (.006-.009) Crystal structure Hexagonal Cutting Emerald and bixbite with heavy inclusions can break apart. Otherwise, beryl is probably the easiest stone to facet. Polishing Beryl polishes easily with alumina or cerium oxide.