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PLASTIC DISPLAY PRODUCTS
PRODUCTS BY WEIGHT
BOX SETS
PLASTIC DISPLAY PRODUCTS
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Obsidian is a naturally occurring volcanic glass derived from a rapidly cooled high silica lava. Often associated with the margins of Rhyolitic lava flows. It has little or no discernable crystalline structure. Specimens are supplied in a polythene bag in lots of 1 kg with a label.
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Obsidian is a natural volcanic glass. An extrusive igneous rock. It is produced when silica rich lava extruded from a volcano rapidly cools minimising crystal growth. Obsidian is commonly found within the margins of rhyolitic lava flows known as obsidian flows. The high silica content (70 -75%) produces a highly viscous lava with some degree of polymerization. The inhibition of atomic diffusion through this highly viscous and polymerized lava explains the lack of crystal growth. It is classed as metastable as over time it will crystalise. Non has been found over Cretaceous in age. Obsidian is hard and brittle with a concoidal fracture it therefore breaks with very sharp edges, which were used in the past in cutting and piercing tools. It has been used experimentally as scalpel blades.
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Snowflake obsidian is quite striking in appearance. It is characterised by the inclusion of radially clustered crystals of cristobalite, which when viewed at a glance, appear like snowflakes on the surface of the rock. These crystal clusters are set in an otherwise black vitreous matrix of obsidian, which is an naturally occurring volcanic glass, even exhibiting a conchoidal fracture. Cristobalite is a high temperature polymorph of silica, it can form as a result of the devitrification of the obsidian. These specimens come from Java, Indonesia and are supplied in card trays, sizes which are optional, each tray also has a small data label supplied.
We also supply Snowflake Obsidian thin sections for microscope study which are available to buy HERE.
Rhyolite Felsite, a highly felsitic composed variation of Rhyolite, found in Scotland. Specimens are supplied in a polythene bag in lots of 1 kg with a label.
Obsidian is an extrusive igneous rock, these specimens exhibit a typical black colouration with conchoidal fractures, they come from South East Mexico and are excellent for educational use and collectors due to the quality. This igneous rock forms when magma extrudes onto the earths surface, chemically it is silica rich and impurities give the black colouration. It’s fine crystalline texture and fracture makes obsidian appear glassy and it breaks as such. The pieces are available in various sizes and come supplied in a card tray with an information label.
We also supply Obsidian thin sections for microscope study which are available to buy HERE.
Mahogany obsidian sourced from the United States of America. Impurities of magnesium and iron give this variety a red or brown appearance hence the name ‘mahogany obsidian’ or oak obsidian. Each Sample is supplied in a labelled card tray.
Out of stock
This Mahogany obsidian is sourced in the United States of America. Impurities of magnesium and iron give this variety a red or brown appearance hence the name ‘mahogany obsidian’ or oak obsidian. Specimens are supplied in a polythene bag in lots of 1 kg with a label.
Out of stock
Graphic granite is an igneous pegmatite rock from Iveland, Norway, which forms in intrusive batholithic bodies that have a felsic composition. As such, the rock is mainly composed of quartz and orthoclase feldspar crystals and lacks any mica, making the rock leucocratic. These samples have what is known as a graphic texture, due to the formation of the crystals, which result in an appearance similar to that of cuneiform text which was once used by ancient human cultures. A brightly coloured, eye catching rock, the samples are suitable for collectors and educational use at higher levels and come available in three sizes. Each specimens is supplied in a card tray with an information label.
91 in stock
Banded rhyolite from Glen Coe, Scotland showing laminar flow banding which was produced by the viscous lava which formed the rock, available in various sizes, these specimens are suitable for educational use to display flow banding. Supplied in a card tray with an information label.
65 in stock
Rhyolite Felsite, a highly felsitic composed variation of Rhyolite, found in Fife, Scotland, an extrusive igneous rock composed of sodium, quartz and feldspar, thus often having a pale white to pink colouration. Available in various sizes and supplied in a card tray with an information label.
32 in stock
This granite pegmatite contains large sheets of muscovite mica, orthoclase feldspar and quartz matrix. An excellent teaching material which comes from Southern Norway. Each specimen comes in a labelled card tray.
Out of stock
Syenite thin section slide. The thin sections show a dominant feldspar mass ( orthoclase ) with occurrences of hornblende, amphibole and clinopyroxene. Biotite mica may also be present however its occurrence is rare, The thin section is supplied in a protective card sleeve with a label, ideal for microscopy and educational purposes.
Click here to to explore our extensive collection of igneous, sedimentary, metamorphic, and mineral thin sections. We offer a wide range of options to cater to your needs. If you require a microscope, you can find them available here as well.
5 in stock
Gabbro thin section exhibiting some of the textbook features one would expect from this coarse, mafic igneous rock. These slides supplement the hand specimens nicely and are useful for interpreting the crystalisation history of the rock.
We provide a full range of igneous, sedimentary, metamorphic and mineral thin sections. Click here to view them. Should you require a microscope, they can be found here.
Out of stock
Specimens of Puddingstone, collected from Hertfordshire, UK. Puddingstone is a variation of conglomerate, which is term used to describe a coarse grained sedimentary rock, featuring large, well rounded clasts in a finer grained matrix. It dates back to the Paleocene to Eocene period around 56 millions years ago. This particular rock is composed almost entirely of silica and has no porosity, likely contributing to its notorious hardness. This rare rock is only found in quantity at one locality in Hertfordshire. As such, it is becoming exceedingly difficult to obtain. This rock is available in multiple sizes and each piece comes supplied in a white card tray with information label.
Big feldspar gabbro thin section exhibiting exactly what its name describes, feldspar crystals much larger than those present in the ordinary gabbro which we supply. Characteristic twinning in the plagioclase and the bright colours of the pyroxene make for an attractive thin section, perfect for educational use.
We provide a full range of igneous, sedimentary, metamorphic and mineral thin sections. Click here to view them. Should you require a microscope, they can be found here.
7 in stock
Obsidian, also known as ‘volcanic glass’ is a felsic, extrusive igneous rock. Crystal growth is minimal / absent within obsidian due to rapid solidification rates which inhibit crystal growth thus giving the rock a glassy appearance.
4 in stock
Pumice specimens from the Lipari islands, Italy. Pumice is an igneous rock with a highly porous structure resulting from trapped gas bubbles as the lava was being ejected. The rock is usually very light & buoyant in water. Specimens are supplied in a card tray with label.
We also supply Pumice thin sections for microscope study which are available to buy HERE.
49 in stock
Rhyolite specimens found in Cumbria. Rhyolite is a felsic (silica rich) rock, often formed in highly explosive volcanoes. Specimens are supplied in a polythene bag in lots of 1 kg with a label.
Hand size specimens of the big feldspar variant of gabbro, samples were collected from Carrock fell, Cumbria, UK and can be supplied in 3 sizes.
We also supply Gabbro Big Feldspar thin sections for microscope study which are available to buy HERE.
66 in stock
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