2021 Sales 8.

 This is a list of slides in stock and available for immediate purchase. Published 21st March 2021.

Please use email - or the contact form on the blog - to  send me a list of the slides you would like to buy, just the slide number will do, and I will reserve the slide for you. A paypal payment request will then be sent, and the slides requested will be sent when payment is received.

Slides will be reserved on a first come first served basis, based on the time stamp on the email/message. the Status of the slide will be changed from Unsold. to Sold. This has to be done manually so there may be a delay. I will confirm by email which slides have been reserved for you.

These slides are fresh stock, recently made, and not from old reserve stock

16559            £14.95            Status:Sold.

This is a thin section of rock from Ailsa Craig, an island in the Firth of Clyde on the west coast of Scotland. Famous for its microgranite that makes the finest curling stones. This rock is from mafic dykes that cut the granite, and is a olivine dolerite with feldspathoid, similar to crinanite which is found on the Isle of Arran, which is not far distant. A very attractive thin section.

16572            £14.95            Status :Sold.

This is a thin section of Granophyre from Dunans on the Isle of skye. Shows excellent granophyre intergrowth between the quartz and feldspars. Minor amphibole, somewhat altered.

16573            £19.95            Status:Sold.

Thin Section Microscope Slide of rock from the Cumbre Vieja volcano, La Palma, Canary Islands. This is the area that is speculated to be the site of a possible flank collapse/tsunami event. Phonolite is an alkali rich, silica poor lava, sanidine feldspar phenocrysts and matrix laths (with volcanic glass) plus brown amphibole and green aegirine both showing good crystal shapes and come zoning and twinning. Numerous but small hauyne, very pale blue with, characteristically, the colour most obvious at the rim. These are isotropic so black in xpl. Very rare mineral.

16575            £16.95            Status :

This is a thin section microscope slide of a Basalt with large pyroxene phenocrysts and smaller olivine ones. Groundmass of plagioclase laths granular magnetite and pyroxene. The pyroxenes have an alteration corona and inclusions of the groundmass, the olivines are quite fresh with iron minerals starting to form along the cracks. This rock is from the shore at North Berwick where lived the hermit St Baldred. Interesting similarity to the Ankaramites from the Canary Islands.

16576            £39.95            Status:Sold.

A thin section slide of Harrisite from the type locality on the Isle of Rum.  Mostly one large elongated olivine,  with pyroxene and calcic plagioclase. some minor alteration minerals, biotite and chlorite showing interesting radiating needles. I suppose technically it is a gabbro but a most exceptional rock.

16578            £24.95            Status:Sold.

This is a thin section of Cassiterite (tin) ore rock from the Golden Dagger mine On Dartmoor, Devon, England. Mainly excellent reddish cassiterite (tin ore) and iron (specular hematite) with blue pleochroic tourmaline in quartz.

This is the best example of cassiterite I have ever come across. This mineral is not easy to find, especially in well formed crystals. I suspect the reddish colour is caused by iron impurities.

16580            £29.95            Status:Sold.

  This is a thin section of a cumulate rock from the Brady Glacier Nunatak, La Perouse intrusion, Fairweather Range, S.E. Alaska USA. Similar to a gabbro/norite from another sample from the same location, but with a higher percentage of mafic minerals, thus now in the peridotite/harzburgite category. Cumulate texture, bright, colourless and totally fresh olivines in plagioclase and orthopyroxene poikilitic textured matrix. The orthopyroxene is in parts gradually altering to red/brown biotite, both parts in the same continuous crystal. Biotite is a hydrous mineral, so water must be present, but the olivine shows no sign of alteration. Interesting.

16581            £19.95            Status:

This is a thin section of Quartz + Tourmaline tin ore rock from an Birch Tor and Vitifer mine On Dartmoor, Devon, England. Mainly quartz with sheavesof pleochroic blue tourmaline,  with small amount of cassiterite (tin ore) and iron (specular hematite)

16585            £19.95            Status:Sold.

This is a thin section of Greisen (altered granite) from Zinnwald, Saxony, Germany. From a tin mining area this is an altered granite containing fans of Zinnwaldite (the type locality, a type of mica), very bright colours in xpl, and Topaz of a type known as Pyknite. This shows characteristic basal parting, and some alteration in the cracks. Very Pretty slide.
This slide contains a large topaz phenocryst, which are fragmented, apart from the natural preexisting basal partings. These topaz have proved difficult to preserve. Slide left very slightly thick for the same reason

16591            £14.95            Status:Sold.

This is a thin section of lepidolite Mica from Brazil. Granular texture, with quartz. Lepidolite is a mauve pink lithium mica. Exceptionally colourful. Maybe slightly thicker than standard.

16611            £14.95            Status:Sold.

This is a thin section of a staurolite containing schist from the shore at Portlethan in Aberdeenshire. Scotland. Not a common mineral in the UK, and not as good as examples from USA or Switzerland, but quite a fair sample all the same. Slide also contains biotite (good radioactive haloes) and muscovite micas, garnet, and quartz. One (at least) green tourmaline present in this slide.

16602            £14.95            Status:Sold.

Thin section microscope slide of a limestone Skarn from Delnabo, Aberdeenshire. This is a limestone, contact metamorphosed by a nearby granitic intrusion and metasomatised. This has produced a number of rare calc-silicate minerals. Vesuvianite, Grossular Garnet, and Diopside being the main minerals but with minor additional ones including wollastonite (never easy to identify in a thin section). Excellent example of a skarn.


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