Sterling Silver,18k Vermeil (gold-plated sterling), Niobium, or Hiirodo Copper. Silver and some Vermeil styles are textured with shiny lines (not black). Niobium is patterned with lines or dots. 18k Gold-Vermeil earwires are left sterling at the top where they rest in your ears and they clip closed in the back.
To see more tiny half-round earrings, search for "tiny half-round batik."
1 1/4" long x 1/2" wide