Properties
| Chemical formula | Ca₂ZnSi₂O₇ |
|---|---|
| Elements | Ca, Zn, Si, O |
| Crystal system | Tetragonal |
| Mohs hardness | — |
| Density | — |
| Streak | — |
| Color | — |
| IMA symbol | Hdy |
| Nickel–Strunz class | 9.BB.10 |
“—” means no reliable value in Wikidata yet. Check Mindat for full data.
✺ Glows under UV
| Longwave UV (~365 nm) | Violet to violet-blue |
|---|---|
| Midwave UV (~310 nm) | Violet to violet-blue |
| Shortwave UV (~254 nm) | Violet to violet-blue |
Found only at Franklin, New Jersey.
Reactions vary by locality and specimen; many specimens of a fluorescent species do not glow. Shortwave UV can burn skin and damage eyes. Wear UV-blocking glasses, and never look into any UV lamp. Sources: Franklin Mineral Museum fluorescent mineral checklist. More UV-reactive stones →
🌍 Where it's found
Type locality (where it was first described): Franklin, United States
- Type locality
- Notable source / deposit
- Country of origin
Marker positions are approximate (region or locality level). Type localities from Wikidata; notable sources curated by Crystopedia.
Learn more
- Hardystonite on Mindat.org
- Wikipedia article
- Wikidata item Q677580 (source of this page's data – you can correct it there)
IMA mineral species
Tetragonal
PinkBrownGrayWhite & Clear
LongwaveMidwaveShortwaveUV reactive