The crystalline minerals occurring within the limits of the Birmingham district may be most conveniently referred to under the titles of the several counties in which they actually occur. These counties are: Derbyshire, Gloucestershire, Leicestershire, Northamptonshire, Nottinghamshire, Oxfordshire, Shropshire, Staffordshire, Warwickshire, and Worcestershire.
Derbyshire.—The mines in this county are worked out, and there is but little opportunity of meeting with minerals. On the spoil-banks of the old mines poor specimens may be found. Mr. John Tym, of Castleton, is a local dealer, and the guide to the High Tor Grotto has minerals for sale. The following list with localities is taken from a paper on “Economic Geology of Derbyshire,” by Mr. A. H. Stokes, F.G.S., H.M. Inspector of Mines. Barytes, nearly all lead mines, Newhaven; Blende, Old hillocks, near Ashover and Hartington; Gypsum, Chellaston, also railway cutting between Trent and Loughborough; Brown Hæmatite, north west of Hubberdale mine, near Taddington, also near Elton; Brown Lead Ore “Linnets,” Elton, and Newhaven, Winster; Calcite, colourless at lead mines of Nether Haddon, near Bakewell. Alpart, Ashover, and Wirksworth yield good specimens. Elaterite, Windy Knoll Quarry, Main Tor, Castleton; Fluor Spar, Blue John and other mines, Castleton; Limonite, a field, one mile north of Castleton, and to the east of Odin Lead mine; Petroleum, Riddings Colliery, near Alfreton. A sump is sunk at the bottom of the mine, and into this the oil finds its way. Some years as much as 100 tons of oil have been obtained at a price as high as £7. 10s. per ton. Phosgenite, very scarce, Meer Brook Sough mine, near Worksworth; Pyrites, large cubic crystals at Gregory mine, near Ashover; Rock crystal, Buxton, in amygdaloid cavities of toad stone; also Diamond Hill, near Miller’s Dale station; Towanite, Old hillocks at Ecton mine, Cumberland mine, Matlock Bath; Wad, mines near Elton; White Lead Ore (Cerussite), near Brassington; Heyspots mine, near Elton; Cabin mine, Newhaven. A more extensive list of the minerals of Derbyshire, compiled by the Rev. J. M. Mello, will be found in “The Midland Naturalist,” Vol. iv., p. 183.
Gloucestershire.—Mr. H.B. Woodward, of the Geological Survey, has given the following list:—Agate, Berkeley, Damory Bridge; Barytes, Tortworth; Bitumen, Clifton; Brown Spar, Tortworth; Celestine, Tortworth, Thornbury, Wickwar, Aust; Fluor Spar, Clifton; Göthite, Clifton; Jasper, Tortworth; Prehnite, Woodford Bridge, Berkeley; Rock Salt (pseudomorphs), Aust; Steatite, Tortworth; Talc, Tortworth; Vivianite, near Clifton.
Pyle Hill, near Clifton, is a well-known locality for Celestine. At Garden Cliff, near Westbury-on-Severn, the “bone bed” is well exposed, and in this bed occurs plenty of iron pyrites; and in the shales, as might be expected, crystals of selenite occur.
Leicestershire.—Gold occurs in the quartz veins round Pedlar Tor, Charnwood Forest. Garnets occur in “gneiss” at Brazil Wood (Mr. W. J. Harrison). Copper pyrites, Molybdenum, Mount Sorrel and Breedon. Galena, Blende, Dimminsdale; Dolomite, Cloud Hill; Gypsum and Selenite, various places; Iron pyrites in cubes, Swithland Great Pit (Mr. James Plant).
Northamptonshire and Oxfordshire.—Barytes, Blende, Calcite, Galena, Glauconite, Gypsum (Selenite), Lignite, Limonite, Pyrites, Websterite, occur in the neighbourhood of Banbury (Mr. Thomas Beesley).
Nottinghamshire.—Gypsum occurs in veins near Retford, and is used for garden rock-work.
Shropshire.—At Lilleshall an old mine known as the Stump Leasow, worked for limestone, yielded the following minerals:[67]—Quartz, a minute crystal only. Erubescite, a few minute patches in the massive form. Copper Pyrites, in sphenoids. Iron Pyrites, in radiating masses. Hæmatite, in minute chocolate-coloured hemispherical masses, also in an almost continual film containing the calc spar and other minerals with a coppery sheen. Barytes, in pink, lamellar, somewhat radiating masses. At the free surfaces of these masses are transparent crystals. Calcite, in beautiful ice-like clusters of crystals taking the form of steep three-faced pyramids. The groups are made up of steep scalenohedrous with rhombohedral summits. The calcite is in some cases pink due to manganese, a sample contained 1·20 per cent. of MnO. In the lower measures the calcite occurs in pointed scalenohedrous lining cavities in the stone. Dolomite, is the most interesting mineral of the group. It occurs in nodules made up of a succession of laminæ of varying diameters, the laminæ crystallizing at the edges in rhombs resembling pearl spar. The composition of one sample of this dolomite is nearly identical with what according to Boricky is one of the possible values of Ankerite. Another approximates to the formula 3 CaCO₃ + (FeMn) CO₃ + MgCO₃ and should be described as a ferriferous dolomite.
In the mining district of West Shropshire many beautiful and interesting minerals are met with. The district is best reached from Birmingham by taking train to Minsterley, via Shrewsbury. At Snailbeach Mine, near Minsterley, occur beautiful rhombs of Calcite, having a violet tinge, due to a small quantity of manganese. There are also crystals of Blende and Galena. At several of the mines Witherite and Barytes are found, and, according to Mr. Morton, other minerals met with are Quartz, Chalcedony, Petroleum, Pyrites, Malachite, Redruthite, Wad, Minium, and Cerussite. At Wotherton, two miles from Chirbury, is a fine barytes lode which has been worked for more than 60 years, at first as an open mine, and subsequently by means of a shaft. The barytes is remarkably pure, and after grinding is sold in large quantities. In the lode are crevices and cavities filled with a fine mud, and penetrating into the mud are fine transparent crystals. These crystals have been measured by Mr. Miers, of the British Museum, and a record of the forms present will be found in his description.[68] (“Nature,” vol. xxix., p. 29.)