Mithral

Mithral is an alloy of pure mithril and bronze. Pure mithril is a soft metalloid that is unsuitable for metalworking, but it adds great strength to bronze and actually decreases its weight. The bronze oxidizes slightly, without a reduction in strength. The final alloy appears a mottled teal color, inlaid with beautiful and subtle patterns. To some smiths, these are essentially random, but the master elven mithral smiths can deliberately cause certain patterns to appear through careful manipulation of the cooling metal.