slaggy

adjective2

1. •
   Resembling or containing slag.

   • Some portions of this obsidian are less compact, and in No, 2. we remark indications of a more slaggy structure, with several white veins intersecting the black surface in a very beautiful manner. — 1834
2. •
   (UK, offensive) Resembling or characteristic of a slag; slutty, promiscuous.

   • This evening I′ve been the cheapest, slaggiest slag ever. — 2005