Toll-Free 888-331-7625 or 307-754-4681 | Shopping Cart | About Us - Company Info | Contact Us Page | Home Page Montana agate slabs $6.60 Montana agate slab samples will contain five square inches per one order. (Stock 536s) Manganese dendrites, moss, bands, or other inclusions of black, green, etc. are in clear to blue gray excellent chalcedony agate. Some of the larger slabs of Montana agate may have a few fractures due to freezing and thawing, but nice large cabochons may still be made from the slabs. The slab of Montana agate pictured to the left contains about 4 square inches in the one slab but at least five square inches will be sent for one order. Related Items Here are some products that may also be of interest to you: • Rough: Montana agate, large