Deposit types
The Rosh Pinah mine has been historically interpreted as being predominantly a reworked SEDEX type deposit comprising a primary banded sulphide exhalite, part of which was carbonatized with associated remobilization and enrichment of sulphides. The secondary carbonate mineralization carries the higher, economic, base-metal values.

The emplacement of the Spitskop Volcanic Complex and related mafic edifices at approximately 752 Ma to 741 Ma drove hydrothermal plumbing along the rift-fault system of the Rosh Pinah Graben. Hydrothermal fluids leached base metals from the basin-fill siliciclastics which were derived mainly from the erosion of a Paleoproterozoic, 2.0 Ga to 1.7 Ga, calcalkaline island arc in the hinterland (Frimmel et al. 2004).

The base-metal bearing brines were exhaled onto the sea floor from the present-day Western Fault bounding the Rosh Pinah Graben, during a period of sediment paucity and / or high sea-level. Exhalation was accompanied by silicification and hydraulic brecciation of the footwall. The primary mineralization was deposited at, or below, the sediment / seawater interface as stratiform, inter-banded, massive sulphide and cherty argillite (micro quartzite). Time between exhalative pulses determined the variation in ratio of content, of chert- exhalite and background argillitic sediment.

At some stage following primary SEDEX style mineralization deposition, the hydrothermal fluid chemistry change ........

Current mining method
Rosh Pinah is an existing operating underground mine with well-established mining methods. The current mining method is LHOS without backfill using a Primary, Secondary, and Tertiary top-down extraction sequence. Mining using this LHOS method since 1969 has resulted in significant voids within the historical and currently mined zones.

Ore is sourced from six steeply-dipping zones, with an increasing proportion sourced from the WF3 and AAB zones, as the eastern zone (EOF) and southern-central zone (SF3, SF3, and BME) are depleted.

Access to the production areas is via multiple interconnecting declines that provide fresh air intake into the mine. A new independent decline from surface to the WF3 zone is proposed.

The current mining areas use a LHOS Primary / Secondary extraction sequence with no backfill, except for WF3, which uses a LHOS Primary / Secondary / Tertiary extraction sequence with no backfill.

The current mining fleet consists of mechanized mobile and ancillary fleet including development jumbos, production drills, loaders and 30 t trucks for haulage to an underground crushing and conveying system (notionally called the Krupp). Future plans include the use of 60 t trucks to haul WF3 material directly to surface.

Current ore haulage is via a decline to the Krupp tip point comprising three ore silos in which to tip. Blending of the ore is conducted using the ore silos to maintain a cons ........

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