This rock contains very numerous nodules of quartz (amygdaloidal), some of which are split into flakes, and others completely fractured. Many of these are white in color and semi-opaque; others have a red skin (jasper), with transparent white quartz within, while others are entirely red. There are also many small, dead grain-like nodules of a white color, as well as ribbon and other agates. In some of the deeper portions of this rock are many small fissures, presenting somewhat the appearance of having been caused by shrinkage; these, in most cases, are distinct from each other, and are filled with white crystallized calcite, or carbonate of lime. Some of the layers of this rock vary in color, and a very compact fine-grained specimen of a reddish color contains amongst other minerals rhombic crystallized carbonate of lime, white; very brilliant iron pyrites, and a mineral looking very much like galena, but harder, of a dark steel gray color, very brilliant, and easily separated into small cubes and laminæ. This is probably specular iron ore. Another mineral has also been found in small quantities, running in veins in the stone, which upon the top appears as having been fused and run, like tin or lead. It is sectile, and of the color of pale bell metal. Very many forms of crystallized carbonate of lime, including “dog-tooth” spar of a pale yellow color are found both in the hard and soft reef, and zeolites of various colors and species, bristling upon and within cavities of the rock. The reef as a whole is fairly even all around the mine, but at the southeast it is very much contorted in the upper layers. The wall formed by the hard rock around the mine is very compact and smooth, and runs inward in some places as much as 30° or 40°, but in others very much less. This naturally causes a cutting out of the claims or a contraction of the mine, but it is said that the blue ground of the Kimberley Central company is now gaining again, and this state of things may also take place with other claims in the Kimberley mine at different depths. (See illustration.) I think this is a fairly full and accurate description of the geological strata outside of the Kimberley mine. I shall now pass on and give a description of the formation of the interior of the mine.