minerals – Page 2 – Emily Zawacki, Ph.D.

mineralogy

Microcline

July 15, 2014August 15, 2018 itssedimentary

Image by author

mineralogy

Vein quartz

July 14, 2014August 15, 2018 itssedimentary

If a channelway for hydrothermal solutions is left incompletely filled with mineral matter, there may be cavities, or “vugs” in the deposit which will be lined with inward pointing crystals. These are quartz crystals, showing mainly the pyramid (or, more exactly, rhombehedron) faces. The quartz was deposited on a rounded surface of hydrothermal hematite (Fe2O3)… Continue reading Vein quartz

mineralogy

Chrysocolla

July 13, 2014August 15, 2018 itssedimentary

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mineralogy

Actinolite

July 12, 2014August 15, 2018 itssedimentary

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mineralogy

Tourmaline in quartz

July 11, 2014August 15, 2018 itssedimentary

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mineralogy

Quartz, pyrite, sphalerite, selenite

July 10, 2014August 15, 2018 itssedimentary

Specimen from Anselmo Mine, Butte, Montana Image by author

mineralogy

Azurite

June 29, 2014August 15, 2018 itssedimentary

Click HERE for more information on Azurite Image by author

petrology

Pegmatite

May 12, 2014August 15, 2018 itssedimentary

Red Ace Pegmatite (WI); Lithium feldspar with pink tourmaline

petrology

Pieces of the Moon!

April 5, 2014August 15, 2018 itssedimentary

Thin sections of lunar basalt (3.15-3.35 Ga) viewed under plane polarized light and cross-polarized light. Sample contains olivine, clinopyroxene, and plagioclase. Images by author

mineralogy

A tale of two CaCO3’s — Calcite and Aragonite

March 14, 2014August 14, 2018 itssedimentary

Aragonite (left) and calcite (right), both CaCO3; image by author Here in this photo, we clearly have two different minerals–one aragonite and the other calcite. However, they both have the same chemical formula of CaCO3. So how can it be that these two different minerals are both calcium carbonate? Aragonite and calcite are polymorphs of… Continue reading A tale of two CaCO3’s — Calcite and Aragonite