Until 1952, sinhalite was thought to be a brown variety of peridot, but on closer investigation it was found to be a completely new mineral. It varies from a pale yellowish brown to a dark greenish brown. Crystals have distinct pleochroism, showing pale brown, and greenish brown and dark brown when viewed from different directions. Although uncommon, sinhalite has been faceted for the collector; Cut stones may be confused with peridot, chrysoberyl, and zircon.

Most-gem-quality sinhalite is found as rolled pebbles in the gem gravels of Sri Lanka. Crystals occur in Burma but arc rare. Sinhalite is also found in the former USSR, and non-gem-quality material in the USA.

Sinhalite is named after sinhala, which is the Sanskrit name for Sri Lanka.