Goshenite
Goshenite is the colorless variety of beryl, Be3Al2Si6O18, lacking the trace-element impurities that give other beryl varieties their color. It crystallizes in the hexagonal system as clear, glassy prisms and takes its name from Goshen, Massachusetts, where it was first described. Historically valued for optical use before high-quality glass was widely available, it is today the least sought-after beryl variety among gem buyers.
Goshenite properties at a glance
| Type | Minerals |
|---|---|
| Chemical formula | Be3Al2Si6O18 |
| Mohs hardness | 7.5–8 |
| Crystal system | Hexagonal |
| Luster | Vitreous |
| Streak | White |
| Cleavage | Imperfect basal |
| Fracture | Conchoidal |
| Specific gravity | 2.65–2.8 |
| Transparency | Transparent |
| Common colors | Colorless, White |
| Rarity | common |
Geology & background
Goshenite forms in the same granite pegmatites that produce colored beryl varieties, but crystallizes where iron, chromium, vanadium, and manganese, the elements responsible for emerald, aquamarine, and morganite's color, are essentially absent or exist only in forms that do not tint the crystal. Because pure beryl is naturally colorless, goshenite represents something close to the mineral's default state, and it often forms alongside colored beryl in the same pegmatite pocket, sometimes even within a single zoned crystal. Notable sources include Brazil, Madagascar, and pegmatites in the northeastern United States near its Massachusetts type locality.
Collectors sometimes irradiate or heat-treat goshenite to induce a blue or yellow tint, so natural, untreated colorless specimens hold particular interest for those studying beryl's chemistry in its unaltered form.
How to identify Goshenite
Goshenite forms hexagonal prisms with a glassy, vitreous luster, a colorless to faint white streak, and, true to its name, an absence of significant body color, sometimes showing only a faint gray or pale yellow tint. Hardness of 7.5 to 8 and a lack of visible cleavage, paired with conchoidal fracture, help separate it from softer colorless look-alikes such as quartz or topaz once other properties are checked. Because it closely resembles clear quartz, careful attention to crystal habit, hexagonal rather than quartz's trigonal prisms with pyramidal terminations, is often needed to confirm the identification.
- Compare the specimen's color, luster, crystal habit, grain size, streak, and locality before confirming.
- Use multiple photos when possible, including a fresh surface and a close view of texture.
Where Goshenite is found
Reported from multiple localities worldwide; verify locality against specimen provenance when available.
How much is Goshenite worth?
| Entry-level specimen | $2 |
|---|---|
| Typical collector specimen | $20 |
| Premium specimen | $150+ |
Value depends on size, crystal quality, color, locality, rarity, damage, and provenance.
Common uses
- Collector specimens
- Education
- Field identification
- Industrial or lapidary use when suitable
Interesting facts
- Before high-quality optical glass became widely available, colorless goshenite was sometimes cut into lenses and eyeglasses.
- Goshenite is essentially beryl with none of the trace elements that color emerald, aquamarine, or morganite.
- The mineral takes its name from Goshen, Massachusetts, where it was first formally described in the early 1800s.
Care & safety
Handle as a collector specimen until hardness, cleavage, and fracture are verified.
Avoid inhaling dust. Do not cut, grind, or polish unknown specimens without eye protection and a proper respirator.
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