Please ID this Rock

[fastnine]

Hey guys does anyone know what ki<a href="http://img284.imageshack.us/my.php?image=dcp30036ch.jpg" target="_blank"><img src="http://img284.imageshack.us/img284/5865/dcp30036ch.th.jpg" border="0" alt="Free Image Hosting at www.ImageShack.us" /></a>nd of rock this is?????

 

[wastememphis]

 

[Mahlhavoc]

Looks like Limestone, something I have used as base rock. If it feels gritty/sandy and is fairly heavy, it prolly is.