Overview

Mine Type	Open Pit
Status	Care and Maintenance
Commodities	Iron Ore
Mining Method	Truck & Shovel / Loader
Production Start	...
Snapshot	The Riley Iron Ore Mine has been on care and maintenance since 2021. The Critica Ltd. carefully considered all options presented and following a competitive process determined that the sale of the Project was the best pathway to unlock the commercial value for Critica shareholders.

Deposit type

• Laterite
• Sedimentary

Summary:

The Riley deposit is a ferruginous laterite derived from weathering of the underlying Wilson River Ultramafic Complex of western Tasmania. The deposits are sedimentary in nature, most likely derived by the erosion of a once thicker veneer of ferruginous laterite covering Serpentine Ridge. There are three significant iron laterite deposits at Riley Creek, namely Areas A, C and D, covering a combined area of approximately 3km2.

The deposits consist of unconsolidated ferruginous lateritic gravel (pisolites) and cemented laterite. The ore is comprised of a combination of hematite and maghemite. The deposit has an average combined thickness of 1.5m, with some areas reaching up to 4m. The laterite deposits are thickest on the ridges, with Areas A and C the most significant of the three deposits. The resource is estimated to be 2.0M tonnes at an average density of 2.5 t/m3.

The in-situ iron grade of the lateritic gravel ranges from 36% to 64% Fe, and the cemented laterite 46% to 61% Fe.

A complete section through the laterite deposits consists of a surficial layer of lateritic gravel (RLG), underlain by a zone of cemented lateritic gravel (RLC)), then ferruginous clay (RCLY) with a variable amount of dispersed ferruginous gravel, minor lenses of lateritic gravel and locally lenses of quartz-rich sand, then greenish and cream clays and finally serpentinite basement. In some locations ferruginous gravel directly overlies clay or, around the margins of the deposits, serpentinite and metasedimentary basement. Sedimentary structures indicate the laterites are essentially colluvial and alluvial deposits most likely derived by the erosion of a once thicker veneer of laterite covering Serpentine Ridge.

Mining Methods

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Comminution

Crushers and Mills

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Processing

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Production

Personnel

Job Title	Name	Profile	Ref. Date
.......................	.......................		Dec 4, 2024