Hello, in todays science assignment, I was told to write about what kind of rock one of the buildings in my town are made of. I could not find one so, I decided to write about a rock I found.
My rock Is smooth and shiny. With some sparkles, and in the shape of a cube, with some missing edges. It has some green stuff in the middle, I am going to crack it open to see what that stuff is.
I have just cracked it open, and their is a green gem in it.
Hypothetically the gem could be: Prehnite, Olivenite, Emerald
After using the tool found at: http://www.minsocam.org/msa/collectors_corner/id/rock_key.htm#granite
I found out that my rock is GRANITE
The table below comes from the website above.
|What Type of Rock Is It? Igneous What Minerals Make Up the Rock? quartz, feldspars (microcline, orthoclase, albite), biotite, muscovite; Sometimes contain: hornblende, augite, magnetite, zircon What Does It Look Like? The feldspars give granite most of its color, which may be white to light gray, yellowish, or pink. The quartz is usually smoky gray or white. Black specks of biotite, or sometimes hornblende, are common. So is silvery to brownish muscovite. Granite is coarse grained to very coarse grained. The crystals are randomly arranged (unlike gneiss where they are in lines or layers). How Was It Formed? Granite forms deep in the earth’s crust from cooling magma. The magma contains a lot of silica (quartz). Slow cooling produces the large crystals in granite. Compare To: gneiss diorite|
So my rock is granite, but I still do not know what the gem in the middle is. I think it might be, most likely, prehnite.
Thank you for reading this essay, I hope you enjoyed. Did you find any rock that had something in it? Anyway, bye and see you next time.