Oxidized sterling, "Raku" Copper, Gold-Vermeil, Sterling Silver or Niobium. With 18k gold-vermeil loops and earwires that are left sterling at the top where they rest in the ear. They clip closed in the back.
Triangles: 1 1/8" long x 5/8" wide
Rectangle: 1 1/4" long x 3/8" wide
To see another size of this style, search for "Small French Loops"