Esperite
A variety of Minerals
What is Esperite?
Esperite is a rare complex calcium lead zinc silicate (PbCa3Zn4(SiO4)4) related to beryllonite and trimerite that used to be called calcium larsenite. It was named in honor of Esper F. Larsen Jr. (1879–1961), petrologist of Harvard University. Esperite has a white, greasy appearance in daylight and is much prized for its brilliant yellow green fluorescence under shortwave ultraviolet light. It is found in association with calcite, franklinite, willemite, hardystonite and clinohedrite. It has also been found as prismatic crystals up to 1 mm in length at the El Dragon Mine, Potosi, Bolivia in association with allophane, chalcomenite, clinochalcomenite and barite.
Optical Properties
- Refractive Index
- 1.760-1.774
- Optical Character
- Biaxial negative
Market Value Factors
Pricing varies for every rock and mineral, so use these universal factors to gauge Esperite before comparing listings or appraisals.
Size & Weight
Larger, intact specimens usually command higher prices.
Rarity & Demand
Scarce material or popular varieties sell at a premium.
Condition & Finish
Chips, repairs, and heavy wear lower value; clean prep helps.
Treatment & Provenance
Untreated specimens with documented locality are prized.
Esperite Localities Map
See where Esperite is found with a localities map, collecting zones, and geology context. Generate a sample map preview below.
Quick Facts
Physical Properties
- Color
- White, off-white, pale tan
- Hardness (Mohs)
- 5
- Density
- 4.25 g/cm³
- Streak
- White
Chemical Properties
- Chemical Formula
- PbCa2Zn3(SiO4)3
- Elements
- Ca, O, Pb, Si, Zn
Identify Esperite Instantly
- Snap a photo, get instant results
- 6,700+ rocks, minerals & crystals
- Discover collecting spots near you
Esperite FAQs
How do I identify Esperite?
Esperite can be identified by its hardness of 5 on the Mohs scale, White color. Look for these key characteristics when examining specimens.
What color is Esperite?
Esperite typically appears in White, off-white, pale tan. Color can vary depending on impurities and formation conditions.
How hard is Esperite?
Esperite has a hardness of 5 on the Mohs scale. This gives it moderate hardness.
%252FAbenakiite-(ce)-01.jpg&size=small)
