Pyrite.

Pyrite.

Pyrite, FeS2, Iron sulphide.  There is not a lot to say about this familiar mineral, except that it is a mineral that is found in nearly all geologic environments. I don't like collecting minerals unless I know exactly where they came from, however this is such a nice specimen that i just could not resist it's purchase. The only information that I have is that it is from Venezuela.  

Calcite.

Calcite.

Calcite, CaCO3, Calcium carbonate is a mineral that is very common in all geological environments. This fist sized specimen is from a mining area in Shropshire. I was walking across a farmers field near Rorington mine, Shelve area of Shropshire, when I stumbled across this specimen. This was about a quarter of a mile from the old mine, and is the only specimen that I found on that day. The major rhomboid crystals have a slight pinkish hue and are totally covered by thousands of minute calcite crystals, and a minor peppering of an unknown black mineral.

Sulphur. ( Sulfur )

Sulphur. ( Sulfur )

Sulphur, S,  is a native element that is abundant in the seas and in the Earths crust and even in the human body. There are over 1000 minerals which have sulphur in their composition, but pure sulphur is not at all common. This specimen comes from Lipari Island, Sicily, which is of volcanic origin. It is massive sulphur with no apparent crystals, and is a mixture of pumice and sulphur. The debris which can be seen in the photograph illustrates that the specimen is very fragile. I have used the older spelling, instead of the American spelling of Sulfur.

Quartz var. Falcons eye.

Quartz var. Falcons eye.

Falcons eye quartz is a blue variety of Tigers eye quartz. It is a parallel intergrowth of quartz and crocodilite which is a common form of asbestos. As with Tigers eye quartz, it also has chatoyant properties which makes it very popular for use in jewellery. This specimen is loosely described as coming from New Zealand, and would display its chatoyant property more vibrantly if it were polished.

Quartz var. Tigers eye

Quartz var. Tigers eye

Tigers eye variety of quartz, SiO2  is formed from by the parallel intergrowth of quartz and altered amphibole fibres which have mostly changed to limonite. Limonite is an iron mineral which gives Tigers eye it's golden brown colour. This specimen is in it's natural form, but would be much more striking in appearance had it been polished, making its chatoyant properties more obvious.  The only information that I have on its origin is New Zealand.