Fundamental Minerals

Sialic Minerals

Feldspar

Feldspathoid

Quartz

Femic Minerals

Accessory Minerals

Very Rare Minerals

Secondary Minerals

Texture

Alteration Products

Glass and related Texture

Volcanic Rocks

Komatiites

Lamprophyres

Kimberlite, Monastery mine, Bloemfontein (S.Africa)

Monastery kimberlite mine is located in the eastern state province (Fig.1). It was discovered in early 1876 by a prospector but was mined before this by local Bashoto tribesman for ilmenite. Large scale mining commenced in 1899. Geologically, the Monastery kimberlite is situated within the Kaapvaal craton along with numerous other diamond-bearing kimberlite fields. Whitelock (1973) described the geology of the mine in detail. The Monastery kimberlite (Fig.2) is an elongated diatreme located along a dyke of 1500 m length; the pipe contained five varieties of kimberlite which Whitelock named quarry, breccia, fine-grained, East-end and South vent type. The south type occurred as blind intrusion which is overlain by 15 m of undisturbed Karoo sedimentary rocks. The Monastery kimberlite is a group I kimberlite pipe of about 0.8 ha in surface area, that intruded Karoo sedimentary rocks. It has been dated 88-90 Ma.

• The East End Type kimberlite is located at the eastern-most tip of the intrusion and was termed the easten blow by Whiteiock (1973). This kimberlite type narrows to a dike-like structure, inclining at shallow depths.
• The Quarry Type kimberlite is the most abundant and most diamondiferous rock type at the Monastery mine (Whiteiock, 1973). Dolerite is found at surface exposures along the southern rim of the Quarry Type kimberlite and also occurs as xenoliths scattered throughout the intrusion.
• The Breccia Type kimberlite forms a column in the central region of the intrusion and has been noted by Whitelock (1973) to have a westerly dip of 70°.

Fig.1: Schematic map of southern Africa showing the location of major kimberlites diamond mines. Modified from Moore et al. (2008)

Fig.2: Schematic map of Monasrtery kimberlites pipe. Modified from Whitelock (1973)

Sample kindly given to me by John Faithfull (Hunterian Museum London)

Bibliography

• E.M.W.Skinner (2009): Devolopments in Kimberlite emplacement theory. The SOllthern African Institute of Mining and Metallurgy Diamonds-Source to Use 2009

Rounded olivine crystals and chromite crystals set in a groundmass composed by calcite. Bloemfontein (S.Africa). PPL image, 2x (Field of view = 7mm)	Rounded olivine crystals and chromite crystals set in a groundmass composed by calcite. Bloemfontein (S.Africa). XPL image, 2x (Field of view = 7mm)	Rounded olivine crystals and chromite crystals set in a groundmass composed by calcite. Bloemfontein (S.Africa). PPL image, 2x (Field of view = 7mm)
Rounded olivine crystals and chromite crystals set in a groundmass composed by calcite. Bloemfontein (S.Africa). XPL image, 2x (Field of view = 7mm)	Rounded olivine crystals and chromite crystals set in a groundmass composed by calcite. Bloemfontein (S.Africa). PPL image, 2x (Field of view = 7mm)	Rounded olivine crystals and chromite crystals set in a groundmass composed by calcite. Bloemfontein (S.Africa). XPL image, 2x (Field of view = 7mm)
Rounded olivine crystals and chromite crystals set in a groundmass composed by calcite. Bloemfontein (S.Africa). XPL image, 2x (Field of view = 7mm)	Rounded olivine crystals and chromite crystals set in a groundmass composed by calcite. Bloemfontein (S.Africa). PPL image, 2x (Field of view = 7mm)	Rounded olivine crystals and chromite crystals set in a groundmass composed by calcite. Bloemfontein (S.Africa). XPL image, 2x (Field of view = 7mm)
Rounded olivine crystals and chromite crystals set in a groundmass composed by calcite. Bloemfontein (S.Africa). XPL image, 2x (Field of view = 7mm)	Rounded olivine crystals and chromite crystals set in a groundmass composed by calcite. Bloemfontein (S.Africa). PPL image, 2x (Field of view = 7mm)	Rounded olivine crystals and chromite crystals set in a groundmass composed by calcite. Bloemfontein (S.Africa). XPL image, 2x (Field of view = 7mm)
Rounded olivine crystals and chromite crystals set in a groundmass composed by calcite. Bloemfontein (S.Africa). PPL image, 2x (Field of view = 7mm)	Rounded olivine crystals and chromite crystals set in a groundmass composed by calcite. Bloemfontein (S.Africa). XPL image, 2x (Field of view = 7mm)	Rounded olivine crystals and chromite crystals set in a groundmass composed by calcite. Bloemfontein (S.Africa). PPL image, 2x (Field of view = 7mm)
Rounded olivine crystals and chromite crystals set in a groundmass composed by calcite. Bloemfontein (S.Africa). XPL image, 2x (Field of view = 7mm)	Rounded olivine crystals and chromite crystals set in a groundmass composed by calcite. Bloemfontein (S.Africa). PPL image, 2x (Field of view = 7mm)	Rounded olivine crystals and chromite crystals set in a groundmass composed by calcite. Bloemfontein (S.Africa). PPL image, 2x (Field of view = 7mm)
Rounded olivine crystals and chromite crystals set in a groundmass composed by calcite. Bloemfontein (S.Africa). XPL image, 2x (Field of view = 7mm)	Rounded olivine crystals and chromite crystals set in a groundmass composed by calcite. Bloemfontein (S.Africa). XPL image, 2x (Field of view = 7mm)	Rounded olivine crystals and chromite crystals set in a groundmass composed by calcite. Bloemfontein (S.Africa). PPL image, 2x (Field of view = 7mm)
Rounded olivine crystals and chromite crystals set in a groundmass composed by calcite. Bloemfontein (S.Africa). XPL image, 2x (Field of view = 7mm)	Rounded olivine crystals and chromite crystals set in a groundmass composed by calcite. Bloemfontein (S.Africa). XPL image, 2x (Field of view = 7mm)	Rounded olivine crystals and chromite crystals set in a groundmass composed by calcite. Bloemfontein (S.Africa). XPL image, 2x (Field of view = 7mm)
Aligned, primary, calcite crystals. Bloemfontein (S.Africa). PPL image, 2x (Field of view = 7mm)	Aligned, primary, calcite crystals. Bloemfontein (S.Africa). XPL image, 2x (Field of view = 7mm)	Aligned, primary, calcite crystals. Bloemfontein (S.Africa). XPL image, 2x (Field of view = 7mm)
Rounded olivine crystals and chromite crystals set in a groundmass composed by calcite. Bloemfontein (S.Africa). PPL image, 2x (Field of view = 7mm)	Rounded olivine crystals and chromite crystals set in a groundmass composed by calcite. Bloemfontein (S.Africa). XPL image, 2x (Field of view = 7mm)	Rounded olivine crystals and chromite crystals set in a groundmass composed by calcite. Bloemfontein (S.Africa). PPL image, 2x (Field of view = 7mm)
Rounded olivine crystals and chromite crystals set in a groundmass composed by calcite. Bloemfontein (S.Africa). XPL image, 2x (Field of view = 7mm)	Rounded olivine crystals and chromite crystals set in a groundmass composed by calcite. Bloemfontein (S.Africa). PPL image, 2x (Field of view = 7mm)	Rounded olivine crystals and chromite crystals set in a groundmass composed by calcite. Bloemfontein (S.Africa). PPL image, 2x (Field of view = 7mm)
Rounded olivine crystals and chromite crystals set in a groundmass composed by calcite. Bloemfontein (S.Africa). XPL image, 2x (Field of view = 7mm)	Rounded olivine crystals and chromite crystals set in a groundmass composed by calcite. Bloemfontein (S.Africa). XPL image, 2x (Field of view = 7mm)	Rounded olivine crystals and chromite crystals set in a groundmass composed by calcite. Bloemfontein (S.Africa). XPL image, 2x (Field of view = 7mm)
Rounded olivine crystals and chromite crystals set in a groundmass composed by calcite. Bloemfontein (S.Africa). PPL image, 2x (Field of view = 7mm)	Rounded olivine crystals and chromite crystals set in a groundmass composed by calcite. Bloemfontein (S.Africa). PPL image, 2x (Field of view = 7mm)	Rounded olivine crystals and chromite crystals set in a groundmass composed by calcite. Bloemfontein (S.Africa). XPL image, 2x (Field of view = 7mm)
Rounded olivine crystals and chromite crystals set in a groundmass composed by calcite. Bloemfontein (S.Africa). PPL image, 2x (Field of view = 7mm)	Rounded olivine crystals and chromite crystals set in a groundmass composed by calcite. Bloemfontein (S.Africa). XPL image, 2x (Field of view = 7mm)	Rounded olivine crystals and chromite crystals set in a groundmass composed by calcite. Bloemfontein (S.Africa). XPL image, 2x (Field of view = 7mm)
Rounded olivine crystals and chromite crystals set in a groundmass composed by calcite. Bloemfontein (S.Africa). PPL image, 2x (Field of view = 7mm)	Rounded olivine crystals and chromite crystals set in a groundmass composed by calcite. Bloemfontein (S.Africa). XPL image, 2x (Field of view = 7mm)	Rounded olivine crystals and chromite crystals set in a groundmass composed by calcite. Bloemfontein (S.Africa). XPL image, 2x (Field of view = 7mm)
Rounded olivine crystals and chromite crystals set in a groundmass composed by calcite. Bloemfontein (S.Africa). PPL image, 2x (Field of view = 7mm)	Rounded olivine crystals and chromite crystals set in a groundmass composed by calcite. Bloemfontein (S.Africa). PPL image, 2x (Field of view = 7mm)	Rounded olivine crystals and chromite crystals set in a groundmass composed by calcite. Bloemfontein (S.Africa). PPL image, 2x (Field of view = 7mm)