These earrings are made using fine silver and niobium.

Fine silver is a higher grade silver than sterling, weighing in at 99.9% silver content compared to sterling's 92.5%. Also, fine silver is far more tarnish resistant than sterling.

Niobium is also strong, corrosion resistant and hypo-allergenic, and can be anodized to beautiful colours, as seen here.

This weave is known as barrel weave.