2021 Sales 2

 This is a list of slides available for purchase. Published 5 Jan 2021.

All slides on this list are sold! New list will follow on Sunday 10/1/21. Please check back.

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.

6059            £14.95        Status:    Sold. 

This is a thin section of Ijoite from the Ice river complex of alkali volcanic rocks in British Columbia, Canada.

Containg clear Nepheline and laths of aegirine. Small amounts of biotite, apatite, calcite with cancrinite vividly coloured in xpl. Numerous bubbles in the adhesive in this slide.

6808            £19.95            Status:   Sold. 

This is a thin section slide of a Stromatolite. These are rarely offered as they are normally legally protected (Rightly). This, and others from Santorini have lived a rather more eventful life than is usual for a stromatolite, having been blasted from their seafloor home by a volcanic eruption and scattered far and wide across the island. This one was collected from a building site. Shows interesting (annual?)growth patterns. Rare.

8466            £19.95            Status: Sold. 

This is a thin section of basalt from the Milne formation in East Greenland. This eruption is associated with the rifting at the start of the opening of the Atlantic, as was the volcanism on what is now the West coast of Scotland. At the time these two land masses were joined, so a comparison of the two basalt types is most interesting. This basalt is en exceptional one in its own right. It is remarkably unaltered, all the minerals are fresh. Numerous well formed olivines and ophitic augite in a mass of plagioclase laths. The whole against a feldspathoidal matrix, which to repeat, is unaltered, which in itself is most unusual. 

10274        £19.95        Status:  

This is a thin section of Phonolite lava from Vesuvius. It contains well formed green pyroxene crystals which show two different types of zoning, growth and sector. Leucite is a large constituent, showing typical faint twinning and grey colours in xpl, clear rounded crystals in plain light. Feldspar (Plagioclase), and small partially altered olivine,  plus other minerals in the groundmass . An interesting slide, slightly thicker than standard to preserve the visibility if the leucite twinning. Pyroxenes are a bit cracked, not unsurprising considering the violent formation of the rock!

16448            £17.95        Status: Sold. 

This is a thin section of a rock from a mine waste dump from a mine in the St Just area in Cornwall. Cassiterite (Tin Ore) is very difficult to identify in hand sample, and several samples I have cut have contained very little or none. This sample contains small granular brown crystals . The matrix of the slide is quartz and also contains numerous blue tourmaline, with growth zoning. 

16517            £10.95            Status: 

This is a thin section of Glaucophane Schist from Longvale, California, USA. Very fine grain makes analysis a bit difficult. Well coloured pleochroic glaucophane makes up much of the composition but several other minerals are present, epidote/zoisite, an unidentified bright green pleochroic mineral, and some small garnets are the most obvious. Lawsonite may be present. The sample has numerous holes and is quite porous. This has resulted in some bubbles, which are going to be difficult to completely eliminate.

16532        £17.95            Status: 

This is a thin section of Hornblendite. A most unusual rock. Collected from the shore at Achmelvich, Scotland. Contains mostly actinolite/hornblende,  silvery pale green in thin section, an absolute riot of colour with crossed polars plus plagioclase. Impressive.

16535            £19.95            Status: Sold. 

This is a thin section of Kentallenite, a rare rock collected from the type location at Kentallen, on the shores of Loch Linnhe, in Scoland. Contains Olivine augite, biotite, and both plagioclase and orthoclase feldspar. Spectacular under crossed filters, the different minerals show up well and are easy to identify except the feldspars, which are a little more challenging. An unusual rock and difficult to classify, probably best called an olivine monzonite. See page 105 Atlas of Igneous rocks, MacKenzie et al. Highly recommended slide , to form part of any collection of Scottish rocks. The photos do not do it justice.

16537            £12.95            Status: Sold. 

This is a thin section of a Rhyodacite rock from the Isle of Rum in the Inner Hebrides. Usually known for it's ultramafic rocks this island has quite a variety of different rock types. This is an acid extrusive rock,thought to be a pyroclastic flow, mainly glassy with flow swirls, but showing minute needles which may be due to devitrification. Phenocrysts of embayed quartz and plagioclase, small amphiboles and mafic area inclusions.

Recent isotope studies suggest that this is formed from Lewisian Gneiss by anatexis

16539            £14.95        Status: 

This is a thin section microscope slide of a dark andesitic tuff showing flow structure from the Bodrum region of Turkey. Contains crystals of plagioclase, pyroxene (augite), biotite mica and rock fragments in a matrix of brown volcanic glass. This shows flow structure. Interesting slide.

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