A Bagley collection introduction.

A Bagley collection introduction.

I have a very large basement area, and this photograph is my store of all things geological, including my collection of rocks, fossils, and minerals. There are many hundreds of specimens, and it will take me a long time to put all of them on the website. Many  minerals  have been collected here in the Central Wales Orefield (CWO). Unfortunately many of the sites have been overgrown, or "landscaped", leaving only a handful of local sites which may still yield the odd specimen.

Specular Hematite with Fluorite

Specular Hematite with Fluorite

Both minerals on this specimen are interesting, The specular variety of hematite ,  Fe2O3  is often referred to by the name specularite.  Specular is a reference to the mirror like property of hematite crystals, which on this specimen, are very small. There are many small clear fluorite,  CaF2  crystals littered on the surface, with an average size of  2.5 mm. On the rear of the specimen is a much larger and better defined area of specularite, with only a small number of fluorite crystals. The specimen is from the Florence mine, Egremont, in Cumbria, which was the last deep working iron ore mine in Europe, finally closing in 2007 after several changes of operator.

Dolomite

Dolomite

Dolomite. CaMg(CO3)2  is an anhydrous carbonate mineral, sometimes referred to as dolostone. It has several industrial uses including the production of float glass, and as an additive to soil and potting mixtures as a pH buffer. This specimen is a tangled collection of tabular crystals with curved faces, which is the normal habit for dolomite . The source of this specimen is from one of the limestone/dolomite quarries in Sligo, Ireland.

Schorl tourmaline

Schorl tourmaline

Tourmaline is a crystalline boron silicate mineral, with 33 different minerals in the group. The most common mineral is schorl, which is a sodium iron end member. Tourmaline is one of the most chemically complicated minerals, so I have chosen not to show the formula. The specimen of quartz has quite a number of schorl inclusions, mostly with the same alignment, and the base of the quartz has an area of iridescence. It is also noted that the quartz is divided by an opaque layer of unknown mineralogy about 1 mm. thick, which the schorl crystals penetrate.  Unfortunately the origin is only listed as Brazil.    

Calcite scalenahedral crystals

Calcite scalenahedral crystals

Calcite,   CaCO3  Calcium carbonate.    There is nothing very special about this specimen, except that it is one of the first specimens I collected many years ago. It is a collection of scalenahedral crystals in a limestone vugh. A few of them on the periphery are slightly larger, and all of them have a dusty coating probably derived from the presence of iron. I collected the specimen from Blaengwynlais quarry, Tongwynlais, Near Cardiff in South Wales