Ask-A-Geologist #8: What is obsidian rock used for?

Hi everyone! Today I am back with another fabulous question from one of our readers. Today’s question is about obsidian. John asks: What is obsidian rock used for?

Ask-a-Geologist Question: Where do Diamonds come from?

Question: Of the three types of rock, igneous, sedimentary and metamorphic, which one are diamonds derived from?

Diamonds are more than a girl’s best friend, they are April’s birthstone too!

Diamond is the hardest mineral, being a 10 on the Mohs hardness scale. Diamonds are found in igneous rocks called Kimberlites, which are formed deep underground (between 90 and 280 miles below the surface of the Earth). This photo shows cores of kimberlite rock from a drilling event. Rock cores are stored in core boxes for examination.

Do you know Volcanic Breccia?

Volcanic Breccia is a unique extrusive igneous rock that is has large, angular fragments stuck in a fine-grained rock background. This rock forms during an eruption when when rock fragments are plucked off of the inside wall of the volcano and are stuck in the lava, or when rock fragments are picked up from the ground by flowing lava.

Our Most Popular Ask-a-Geologist Question…..EVER!

This has to be the most-asked question we receive here at Mini Me Geology. Question: What are the hollow ball-like objects, such as quartz, which are found in sedimentary rocks?

What are some household items made out of igneous rock?

Igneous rocks are often used as building materials and in the production of household items.