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Red, Purple or Roman Imperial Porphyry rock

Purple, Red, or Roman Imperial Porphyry

Purple, red, or Roman Imperial porphyry refers to reddish to purplish porphyritic rocks highly-priced during the antiquity age by Romans

Categories Rocks
How to break, crack or open a geode - half cut

How to Crack, Break or Open a Geode Like a Pro

Would you like to know how to open a geode? The common ways are smashing it, using a crack hammer

Categories Rocks
Geode in Illinois from Lower Warsaw Formation in Hancock County - Mississippian Age

Where to Hunt for Geodes in Illinois

The best places to find geodes in Illinois are Warsaw, Hamilton, and Nauvoo, which are areas in western Illinois that

Categories Rocks
What are Geodes

What Are Geodes? Their Uses, Colors, and Mineral Crystals?

Geodes are hollow or partially filled, roughly spherical structures, globular or oblate spheroidal discrete bodies or structures lined with mineral

Categories Rocks
How are geodes formed

How Are Geodes Formed in Nature?

Is your question how are geodes formed in nature? The simple explanation is the process involves 1) cavity formation and

Categories Rocks
Geodes vs. thundereggs, nodules, concretions, vugs. sperulites

Geodes vs. Thundereggs, Nodules, Concretions, and Vugs

Since they resemble each other, it is good to discuss geodes vs. thundereggs, nodules, vugs, concretions, and other similar structures

Categories Rocks
What are lithophysae

What Are Lithophysae and How Do They Form

Lithophysae (singular lithophysa) are roughly spherical to lenticular-shaped structures with onion-like shells and a hollow center. These structures, which occur

Categories Rocks
Coarse-grained medium to dark diorite rock with a salt and pepper appearance

Diorite Texture, Composition and Uses

Diorite is a coarse-grained intermediate plutonic rock. Intermediate are rocks whose composition lies between felsic and mafic. Felsic rocks are

Categories Rocks
How diorite and gabbro differ

How Does Diorite and Gabbro Differ?

Both diorite and gabbro are coarse-grained rocks. They both form from the slow cooling of magma. This slow cooling allows

Categories Rocks
Spherulites in obsidian clast breccia

What Are Spherulites and How Do They Form?

Spherulites are small, spheroidal, or globular structures common in glassy volcanic rocks. These bodies have dense masses of tiny, fibrous,

Categories Rocks
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