Re: Re: Igneous or Synthetic?
Thank you for your reply Don!
The first material is the same on all sides (bubbles).
The 2nd rock isn't layered - but does have some grains stuck to the bottom (like lava poured over a grainy surface). There's also a tiny white surface line like I've seen on some other rocks (like a thin white winding string). What causes that? Thank you for identifying the little "egg" formations! Very cool!
Is pumice ever black? I found a light-weight, squarish shape, floating black "rock". Pencil-like mark when scratched on white tile. Pumice or some type of "rock" for gas grill?
Another question - I find small dark rocks by the railroad tracks that are white-bluish in color when broken open. The surface is powder-like dark brown that easily wipes off. Is this a type of iron ore? Has it been processed in any way or natural?
I also found a light weight rounded black rock that has a soft feel and pieces easily break off. Is this a type of coal or volcanic rock (found it on the Virginia coast).
Many thanks for your help!
From CubScoutMom - April 15, 2008 at 08:12:31