Natrolite and Microcline - Mont Saint-Hilaire, Quebec, Canada
Contributed by: FMS Admin
minID: VG4-M5N
Date: May 18th, 2026
Locality: Poudrette quarry (De-Mix quarry; Demix quarry; Uni-Mix quarry; Carrière Mont Saint-Hilaire; MSH), Mont Saint-Hilaire, La Vallée-du-Richelieu RCM, Montérégie, Québec, Canada (See on Mindat)
Size: 9.4 x 8 x 12.8 cm
Description:
Shown here is a nice cluster of translucent natrolite crystals, associated with misshaped microcline crystals. As usual, the natrolite crystals show a bright green uranyl-activated response under shortwave UV. As is usually the case, only the tip of the natrolite crystals fluoresces under SW. The natrolite also fluoresces under midwave but SW is the brightest. The microcline fluoresces the typical dull red response of feldspar. While not being among the most spectacular MSH natrolites, this specimen is nice both under UV and white light, unlike so many of our glow rocks! Non-fluorescent light brown siderite is also present.
Originally posted by Frédéric Messier Leroux on Nature's Rainbows in 2021.
Summary of luminescence responses:
Microcline (Mindat) (RRUFF)
- Fluorescence under Shortwave (255nm LED) UV light: Red
- Fluorescence under Shortwave (255nm LED) UV light: Green