I found this in the river...and i'm wondering what kind of rock can be shaped like this..... (Greenfield: summer)

[Samayo]

So i'm a river rat....this summer we were in a river in Greenfield and I found this rock...it's really heavy but I lugged it up the hill anyways because i like how it's shaped wierd...kinda like a hip bone..... I have yet to take it to the discovery center or library in Turners Falls but I did email a GCC professor and am waiting to hear back from him....what do you all make of it?


http://i216.photobucket.com/albums/c...an/sept217.jpg


http://i216.photobucket.com/albums/c...an/sept216.jpg

[bryfry]

Looks like a piece of limestone that was in the river for quite some time. Being a sedimentary rock, it probably will erode faster in running water (compared to granite for example), therefore creating the strange shape. Limestone has a harness factor of 3 and granite has a 7 or 8.

Just a guess. Let us know when you find out.

[litlux]

I think bryfry got it right, some form of calcium carbonate, likely limestone, and shaped by running water.

Could have originally been a small stone deposited as glacial till.

[bryfry]

Originally Posted by bryfry

harness

Ugh! I meant harDness!

I need to proof read better!