Imperial Valley Guitar Co. specializes in resonator guitars and acoustic Hawaiian guitars. This is a new product from them that goes right along with their resonators. Its a slide thats made from stone. This is a slide that is literally made from rock. The onyx stone is drilled and turned on a lathe to make a really unique and cool sounding slide.
Tone-wise the Blackstone slide is warmer and not as whiney as a glass slide and has less string noise. The sound is somewhere between brass and glass. Even though it is are actually made from stone, its not especially heavy. Even with the extra thick walls its still only 2.2 ounces, lighter than a heavy wall brass or steel slide.
Dimensions:
60mm (2 3/8") long
28.5mm (1 1/8") outside diameter
19mm (3/4") inside diameter
4.75mm (3/16") thick walls
#9 ring size
2.2 oz weight
Equivalent to medium size, heavy wall in glass slides