Factsheet 10 – What are the challenges of opal mining?

Australian Curriculum Links Quirky fact : Year Subject Curriculum Links When boulder opal 5 Geography ACHGK028 is cut and polished 7 Geography ACHGK043, ACHGK044, ACHGK040 some of the ironstone Science ACSSU116, ACSHE121 is always retained 8 Geography ACHGK050, ACHGK056

as a natural backing. Science ACSSU153, ACSHE136

Background Information Australia produces 96 per cent of the world’s opals. other more common opal types include: Opal was first mined south of Quilpie in 1871, following its Matrix opal – where the opal occurs as discovery at Listowel Downs near Blackall in 1869. Today, a network of veins between grains of the host Quilpie remains the largest miner of opal and the only rock (ferruginous sandstone or ironstone); producer of the ironstone boulder opal. Seam or band opal – usually found The opal fields of Outback follow a 300 km- encased in ironstone; wide belt of deeply weathered Cretaceous sedimentary Pipe opal – which may be up to several rocks known as the Winton Formation. This belt extends centimetres in diameter within the sandstone; and a distance of about 1,000 kilometres from Hungerford on the New South Wales border, west of the townships of Wood opal – sometimes found replacing , Quilpie, Longreach and Winton, to Kynuna. woody tissue material. Boulder opal is unique to Queensland and widely Large mines are mostly open-cut operations. distributed in the weathered sandstone rocks common to Boulders are carefully removed from the ground for these areas. In general, finds can range in size from a few processing and heavy equipment is often used to open centimetres to three metres across. up old workings. Underground mining is also practised Opal acts as a lining between the concentric layers or and shafts are sunk to detect any intersecting layers cracks of ironstone. Sometimes it appears as a kernel beneath the ground surface. Miners use light machinery in smaller concretions or nuts – hence the term ‘- to remove the boulders, at which point they are checked nuts’. While boulder opal is only found in Queensland, for opal content and sorted for sale or further processing.

Opal education, Winton

70 Outback Queensland Education Handbook | Australian Curriculum Factsheets Inquiry Questions

Subject Years Questions ADDITIONAL RESOURCES Geography 5/6 How has the environment influenced the Tourism Queensland characteristics of mining communities? Source: General Outback information www.adventureoutback.com.au

7/8 How do opals form? The Mineral and Gemstone Kingdom How do remoteness and scarcity of water www.minerals.net/mineral/opal.aspx influence the characteristics of mining REFERENCES communities? Queensland Department of Natural Read a daily newspaper and write down everything Resources and Mines www.dnrm.qld.gov.au/ you can find related to mining in Queensland/ Australia Opals Down Under www.opalsdownunder.com.au/learn-about- Science 7/8 How do opals form? opals How does scientific understanding help people Opal Bar Map www.opalbar.com.au/index. live, work and manage resources in the Outback? php?act=viewDoc&docId=5

FURTHER INFORMATION Points of Interest Department of Mines and Energy Gem Fossicking, Quilpie Information Centre Quilpie has fossicking at Duck Creek and Sheep Station Creek opal fields. Level 2, Mineral House 41 George Street, QLD 4001 Quilpie Museum and Visitor Information Centre Phone: (07) 3237 1434 Brolga Street, Quilpie QLD 4480 For information contact the Quilpie Visitor Information Centre for maps and permits or contact the Department of Mines and Energy at www.dme.qld.gov.au Cost: Fees and licenses apply Hours: By appointment Phone: (07) 4656 1133 Email: [email protected] Website: www.quilpie.qld.gov.au Please note: All mining activity is covered under Acts administered by the Department of Natural Resources and Mines. Permission is required before entering an area held under mining tenure and a Prospecting Permit is usually required. Gem fossicking, Opalton Gem fossicking, Yowah

r r W 109 a OOTA e W k v e i AUGATHELLA 40 e R ADAVALE 40 r 158 C o 187 Haddon r o INJUNE e l 109

p l o 84 91 Corner o u C 85 B 85 87 MORVEN 91 QUEENSLAND CHARLEVILLE 44 MITCHELL 22 QUILPIE 74 CHEEPIE 88 TREGOLE 69 NATIONAL MUNGALLALA 45 AMBY 37 PARK 65 ROMA EROMANGA 48 COOLADDI 99 74 167 161 209 e r v 210 Townsville i WYANDRA R TOOMPINE 210 195 Mt Isa n 36 180 o Rockhampton s Longreach l DIG TREE 5 i 55 W 120 82 98 20 Charleville BRISBANENOCCUNDRA 23 25 46 7 YOWAH CUNNAMULLA 191 13 177 BOLLON 113 131 68 ST G

Outback Queensland Education Handbook | Australian Curriculum Factsheets 71