05-28. Scapolite #1.
Scapolite – a strange and very busy mineral!

Hard to capture, it comes in many colors. Its structure leads to an odd and complex geometry. It will be the mineral of week #22 of this 52 weeks tour of the geometry of Nature.

The scapolite group includes crystals such as meionite, marialite, and silvialite. The name comes from the Greek skapos (shaft) because of the stumpy nature of its crystals. Colorless in its pure form, inclusions give it a bluish gray, greenish yellow, pink, violet, golden yellow color.

It belongs to the tetragonal system – three axes at right angles, two of them equal.

The best scapolites have been found in Madagascar, Myanmar, Tanzania, Tajikistan, and Peru.

This one is a combination of the crystal’s atoms, polyhedra and Van der Wall effect from a resource by Levien & Papike.



05-27. Iolite – cordierite #7

Last day of the iolite. I’ll be missing its unique and inviting symmetry. I could work endlessly from the patterns of its cell structure. Maybe some future project…

From a resource by Malcherek, Domeneghetti, Tazzoli, Ottolini, McCammon and Carpente. A cordierite crystal from Zimbabwe.



05-26. Iolite – cordierite #6

Tessellation of an iolite unit cell polyhedra pattern. Center: iolite atoms in a cube.

From a resource by Malcherek, Domeneghetti, Tazzoli, Ottolini, McCammon and Carpenter. Great Bear Lake, Canada.



05-25. Iolite – cordierite #5

The is something so unique about the iolite structure – I could use it as an endless source of inspiration if I was a sculptor!

From a resource by Sokol, Seryotkin and Bul’bak. Cordierite from the Murzinka pegmatite field, Middle Ural Mountains, Russia.


05-23. Iolite – cordierite #3

Iolite unit cell, atomic arrangement & connection. It looks like an astronomer’s sky or planetary map. The very small and the very large are not that different. Background: tessellation of the same iolite unit polyhedral structure.

From a resource by Armbruster, single-crystal study from Ruby Island, New Zealand.