Adamantine lustre Adamantine minerals possess a superlative lustre, which is most notably seen in
diamond. Such minerals are transparent or translucent, and have a high
refractive index (of 1.9 or more). Minerals with a true adamantine lustre are uncommon, with examples including
cerussite,
zircon, and
cubic zirconia. A distinction is sometimes drawn between dull minerals and earthy minerals, with the latter being coarser, and having even less lustre.
Greasy lustre Greasy minerals resemble fat or grease. A greasy lustre often occurs in minerals containing a great abundance of microscopic inclusions, with examples including
opal and
cordierite,
jadeite.
Metallic lustre Metallic (or
splendent) minerals have the lustre of polished metal, and with
ideal surfaces will work as a
reflective surface. Examples include
galena,
pyrite and
magnetite.
Pearly lustre Pearly minerals consist of thin transparent co-planar sheets. Light reflecting from these layers gives them a lustre reminiscent of
pearls. variety of
gypsum Silky lustre Silky minerals have a parallel arrangement of extremely fine fibres, and occurs in transparent or translucent minerals with relatively low refractive indices. and
chalcedony. ==Optical phenomena==