The Orion occurrence is located in Orion Creek valley, approximately 3 kilometres north of the Swannell River valley and about 111 kilometres north-northwest of the community of Germansen Landing.
Regionally, the area is underlain by a series of northwest trending sedimentary rocks of the Neoproterozoic Ingenika Group and include argillite, greywacke, wacke and conglomerate turbidites of the Swannell Formation, mudstone, siltstone, shale and fine clastic sedimentary rocks of the Tsaydiz and Stelkuz formations and limestone, marble and calcareous sedimentary rocks of the Espee Formation. To the southwest volcaniclastic rocks of Permian age and fine clastic sedimentary rocks of Mississippian to Pennsylvanian age, both of the Lay Range Assemblage are exposed.
The showings are hosted in grey and brown, medium to fine-grained, steeply dipping, well bedded, micaceous quartzites of the Neoproterozoic Ingenika Group. The quartzites are cut by a few aplite dikes up to 1 metre wide and contain massive white quartz veins parallel with the bedding planes. The quartz veins are cut by smaller veins of smoky grey quartz that in some places contain scattered crystals and irregular bodies, up to 30 by 10 centimetres, of galena and lesser tetrahedrite. The overall sulphide content is low.