Bone charcoal with just the right sieve size for crucible packing of steel parts to be hardened. Hi-carbon content without waxes or fillers gives brilliant color patterns. Mixing types of charcoal (bone and wood) by specific ratio provides additional control over color and pattern.

SPECS: Packed in 5 gal. bucket. Bone - 10x28 sieve size, 25 lb. (11kg) weight.