Cortosis weave

Cortosis weave was a rare, energy-resistant mesh that some armorers shaped cortosis ore into. Cortosis weave made armor nearly impervious to penetration by energy weapons, including not just blasters, but also lightsabers. Even if cortosis ore was not available, other substances like Mandalorian iron, phrik alloy, and ultrachrome had similar effects if properly treated, though they tended to add considerably more weight to a suit of armor than cortosis weave.

Text and facts from the “Cortosis weave” article on Wookieepedia, licensed under CC BY-SA 3.0. Modified for this site.