#euhedral
One of the entrances to Jewel Cave. It's filled with euhedral calcite crystals with distinct "jewel-like" structures. Jewel Cave National Monument, South Dakota, 30 Jul 2025.
July 31, 2025 at 4:18 AM
One of the entrances to Jewel Cave. It's filled with euhedral calcite crystals with distinct "jewel-like" structures. Jewel Cave National Monument, South Dakota, 30 Jul 2025.
January 23, 2026 at 11:09 PM
Spent all day putting together a presentation about the collections.

Please enjoy some euhedral almandines in matrix from Alaska
April 29, 2025 at 10:55 PM
A typical euhedral crystal of hornblende in the wall cladding of the Daisen Museum of Nature and History.
August 9, 2026 at 7:49 AM
Now I want a pretty, plain, euhedral feldspar crystal. 😕
August 17, 2026 at 8:11 PM
An Ethiopian #sapphire displays serene blues with euhedral #zircon and #monazite inclusions.

Can wavellite do this?

www.gia.edu/gems-gemolog...

#MinCup #Corundum
September 18, 2024 at 3:21 PM
Spectacular olivine dolerite from Fair Head, County Antrim in XPL for #ThinSectionThursday. Olivine shows particularly vibrant interference colours while the ophitic intergrowth of twinned plagioclase and clinopyroxene is a textbook quality example. 🧪⚒️🌋
March 5, 2026 at 10:31 AM
Super mature quartz arenite with well rounded detrital quartz and euhedral quartz overgrowths.

Neoproterozoic Panem Quartzite, Cuddapah Basin, South India.

#ThinSectionThursday

🧪
January 23, 2025 at 10:45 AM
I want to seem euhedral what is that
February 2, 2026 at 6:02 PM
(They're actually quite pretty when they're euhedral. It's just they're basically never euhedral.)
August 17, 2026 at 8:12 PM
*also have a beautiful #cinnabar*

#MineralCup #MinCup23 #MinCup2023
September 2, 2023 at 10:11 PM
Guy that wants to seem super cool and euhedral: I don't even know who that is
February 2, 2026 at 5:58 PM
Sodalite-rich portion of lajuvrite from Ilimaussaq, Greenland. Large, euhedral (isometric) sodalite crystals are black in XPL. Interstitial aegirine augite shows green masking over strong interference colours. Collected by the late Henry Emeleus #ThinSectionThursday 🧪⚒️
September 18, 2025 at 1:00 PM
Olivine- and plagioclase-phyric, vesicular basaltic glass in cross polarised light from Hawaii for #ThinSectionThursday. Olivine shows wide range of interference colours despite uniform composition. Much of the glassy groundmass is devitrified in rosettes around the phenocrysts. 🧪⚒️🌋
May 21, 2026 at 8:51 AM
(Long) Before mobile phones: hand drawn PPL and XPL views of porphyritic dolerite from Ben Hiant, Ardnamurchan, Scotland. From my undergraduate mapping report. #ThinSectionThursday 🧪⚒️🌋
February 5, 2026 at 10:46 AM
Late Miocene basalt with cool euhedral olivine and scattered pyroxene. Crossed polars 40X. Comstock Mining District, Nevada. Taken with AO 110 Polstar. This is another target source for use in permanent carbon sequestration. #thinsectionthursday #geology #volcanic #rocks #mineral #climatechange
January 9, 2025 at 11:01 PM
I'm going with #Cassiterite ! Here with quartz and ankerite. From a friend's collection #MinCup26 ⚒️ #minerals
September 17, 2026 at 12:25 AM
Today's challengers are both formidable.

But I'm choosing corundum because it goes so hard.

#mincup24
September 18, 2024 at 2:20 PM
Sorry about your skull product. It's still largely intact thankfully, but it's since lost the edges and euhedral crystal faces that made it so alluring.
September 9, 2026 at 8:43 AM
Revisiting this Honolulu Volcanics mantle xenolith which has a porphyroclastic texture. Note the bimodal grain size distribution of the olivines with large subhedral porphyroclasts and smaller relatively euhedral neoblasts in the matrix.

#xenolith #peridotite #geology ##geoscience #olivine
December 2, 2025 at 12:13 AM
Extraordinary large euhedral #Augite in leucocratic volcanite at #Tenerife, #Anaga mountains near Benijo.
February 1, 2025 at 7:26 PM
Dexter is euhedral, no amount of change in the universe would prevent it from coming out.
June 5, 2026 at 5:34 AM
Just look at this tiny baby time capsule.

JUST LOOK AT IT

#MinCup23
September 29, 2023 at 1:14 PM
Wooo
February 6, 2025 at 7:15 PM