Situated in NSW, Australia, about 500 km inland from the
coast, 760 km north-west of Sydney, and 750 km south-west
of Brisbane, 1200 km north of Melbourne, and about 800
km north of Canberra, very central really. :-)
The town is on a ridge of about 50 m height above the surround
desert that is approximately 120 m above sea level, so the highest point on the ridge is 174 m asl, which
in geological antiquity was actually a sea basin where deposits
of sand and mud formed.
Over time these layers were infiltrated
by heated silica water and opals formed,
and as the land was lifted and eroded
away, the harder sandstones remained
forming the ridge.
The opals found here are unique and worldwide the most
prized, and hence very valuable, as they are black background,
with many colours inlaid, a very unique occurrence, as most
opal in the world has only one colour at a time. The red
on black opals are the most valuable and has made many
people very wealthy. Many more of course have poured their money
into holes in Lightning Ridge and either barely survived
or gone broke.
A variety of opals can be seen on the information video,