If you are looking for something 100% natural with a rustic and rugged look to it, Irregular flagstone is what you need. With so many colors to choose from, why would you go with anything else? Flagstone runs 18"-72" in diameter and 1"-3" thick depending on color you choose. Retail Prices at the bottom of the page.
NY Bluestone Full color
1 1/4" - 2 1/4" Thick
Chilton
1 1/2" - 2 1/2" Thick
Colorado Rose
1 1/2" - 2" Thick
New Mexico Buff
1 1/2" - 2 1/2" Thick
Tennessee Crab
Regular 3/4" - 1 1/2"
Heavy 1 1/2" - 2 3/4"
Colorado Silver
1 1/2" - 2 1/2" Thick
Cheyenne Blue Slabs
2" Thick
Frontier Sandstone
1" or 2" thick
Mahogany Regulars
2" Thick