In 1845 the celebrated Burra Burra mine was discovered.
The Wallaroo and Moonta mines, discovered in 1860 and 1861, proved to be even more valuable than the Burra Burra, the Moonta mines employing at one time upwards of 1600 hands.
Besides Mainland, the principal member of the group, the more important are Yell, Unst and Fetlar in the north, Whalsay and Bressay in the east, Trondra, East and West Burra, Papa Stour, Muckle Roe and Foula in the west, and Fair Isle in the south.
East Burra (203), about 4 m.
West Burra (612), 6 m.
Broad, with a very irregular coast-line, lies alongside of East Burra and contains a church.
Burra is a contraction of Bo?gar-oy, meaning "Broch island."
Burra Firth, in the north of Unst, is flanked on both sides by magnificent cliffs, including the Noup of Unst, the hill of Saxavord (934 ft.), the Gord and Herma Ness.
Adelaide is also the central share market of Australia, for West Australian goldmines, for the silver-mines at Broken Hill, and for the coppermines at Wallaroo, Burra Burra and Moonta; while Port Adelaide, on the neighbouring shore of St Vincent Gulf, ranks as the third in the Commonwealth.