Sold by the Bag (1 Quantity = 5 Pounds) This is a few chunks of 99.6% minimum purity Antimony that is broken off a larger ingot, 5 pounds total in a few pcs. The is no set size for the chunks of antimony, but your shipment will equal the amount you ordered. The melting temperature is 1167 F. Physical Information Atomic Number - 51 Relative Atomic Mass (12C=12.000) - 121.75 Melting Point/0F - 1166 Boiling Point/0F - 2516 Density - 6.62 Weight Lb/in3 - 0.2391