hematitic

The remaining 20% is oxidized and consists of three hematitic ore types.

Hematitic alteration of the sediment that resulted from baking by the lavas is minimal, amounting to a few centimeters or less.

The main hematitic ore is medium- to fine-grained and displays a variety of massive, banded and porous textures.

The formation of hematitic jasperoids is considered to be the product of highly oxidised metasomatism of the wall rocks to a shear zone.

Some hematitic jasperoids may be sourced from metamorphosed and altered jaspillite, and are located above areas identified as submarine basalt vents.

The formation is composed primarily of red and grey hematitic, sandy, calcareous and argillaceous shales with localized greenish banding.

Jasperoid is a rare, peculiar type of metasomatic alteration and occurs in two main forms; sulfidic jasperoids and hematitic jasperoids.

Hematitic jasperoids are examples of advanced silica-hematite alteration, and are known only from the Proterozoic rocks of the Glengarry Basin in Australia.

Hematitic jasperoid is only found within the Glengarry basin, Western Australia, although it probably represents an end-member state of a variety of alteration and metasomatism styles found elsewhere.

The deposits are anomalously high in iron for deterital material, and exclude detrital iron deposits typified by scree of hematitic banded iron formations and accumulations of currently-forming maghemite pisolite alluvials.