| TERM |
MEANING |
| Agitator |
Modified cement mixer used to wash dirt away from precious opal. |
| Boulder Opal |
Formed in cavities and cracks of ironstone, usually from NSW, Australia. |
| Black Opal |
Naturally occurring solid opal with a coloured face and black backing. |
| Blower |
A large truck-mounted vacuum cleaner used to suck dirt to the surface. |
| Cabochon |
The rounded surface of a cut stone. |
| Chinese writing |
Type of opal pattern with criss crossed strokes of colour looking like oriental letters. |
| Crystal |
Transparent/translucent opal. |
| Doublet |
Opal with an attached dark coloured backing. |
| Drive |
A horizontal underground tunnel. |
| Free-form |
A naturally shaped opal - something other than an oval or round shape. |
| Gouge |
Mine slowly with a pick, nowadays usually only when opal is known to be present. |
| Harlequin |
Type of opal pattern with a checkerboard appearance, rare and expensive. |
| Hoist |
A bucket attached to a framework in a shaft, used to carry dirt to the surface. |
| Jelly |
A type of opal with indistinct, fuzzy colours. |
| Level |
Usually the layer of opal bearing dirt. |
| Matrix |
Any material with specks of opal running through it. |
| Muggie |
A cheap solid opal, having little colour or brightness. |
| Mullock heap |
Mound of opal dirt dumped by a miner on the surface. |
| Nobby |
Nodule of opal almost exclusively from Lightning Ridge. |
| Parcel |
A collection of any number of opals, either rough, rubs or cut, offered for sale. |
| Pinfire |
Type of opal pattern where specks of different colours cover the whole stone. |
| Potch |
Opal without any colour, also called common opal. |
| Puddler |
Forerunner of the agitator, a mesh drum. |
| Ratter/ratting |
Thief/thieving from someone else’s mine (a serious offence). |
| Ribbon |
Type of opal pattern with the colour running in stripes. |
| Rough |
Opal in its natural state; as it comes out of the ground . |
| Rubs |
Opal pieces initially shaped with waste material/sand removed but not yet cut and polished. |
| Rumbler |
Revolving mesh drum to sort opal from dirt, now superseded by the agitator. |
| Seam |
Opal found in a layer rather than in nobbies. |
| Shaft |
A vertical hole down to a mine. |
| Solid |
A naturally occurring solid piece of opal, cut into a stone. |
| Sunflash |
Opal showing colour only from certain angles when exposed in light. |
| Specking |
Searching through abandoned heaps of opal dirt – also called noodling. |
| Tailings |
Material left after opal dirt from the mine has been washed. |
| Tail out |
Search through tailings. |
| Tank |
Dam of water on which agitators are located. |
| Triplet |
A stone comprising a thin layer of natural opal with an attached dark backing and a clear capping. |
| Windlass |
Forerunner of the hoist – hand operated device for raising buckets of opal dirt to the surface by means of a cable around a drum with handles. |
| Yowah Nut |
Small ironstone boulder, containing opal either as a solid kernel or in concentric layers. |
Opals