Shiny rock

[Kewlworm]

I just cracked open a rock with a screw drive and a hammer...it was harder than I thought.

Anyway, the inside has is shiny/sparkle when light hit it. Anyone know what it is? I saw it at school once, but forgot what it called. It couldn't be aragonite.

Thanks!
Gary

 

[astrogazer]

My first guess would be Calcite (Calcium Carbonate).

 

[Ludwigia73]

hard, with a shiny sparkle to it? Maybe quartz

 

[chrisaggie]

Most likely calcite.

 

[Kewlworm]

I think Calcite is what it is.

Thanks guys!