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PRODUCTS BY WEIGHT
BOX SETS
PLASTIC DISPLAY PRODUCTS
PRODUCTS BY WEIGHT
BOX SETS
PLASTIC DISPLAY PRODUCTS
£2.25 – £6.00 ex VAT
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.
We ship to all 50 states, Washington DC.
All orders are shipped with a UPS tracking number.
Always free shipping for orders over US $200.
During sale periods and promotions the delivery time may be longer than normal.
Elessi will accept exchanges and returns of unworn and unwashed garments within 30 days of the date of purchase (14 days during the sales period), on presentation of the original till receipt at any store where the corresponding collection is available within the country of purchase.
Your return will usually be processed within a week to a week and a half. We’ll send you a Return Notification email to notify you once the return has been completed.
Please allow 1-3 business days for refunds to be received to the original form of payment once the return has been processed.
Give us a shout if you have any other questions and/or concerns.
Email: contact@mydomain.com
Phone: +1 (23) 456 789
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 which gives the rock a fine, glassy texture. It is commonly found within the margins of rhyolitic lava flows known as obsidian flows, its 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 hard and brittle rock with a black appearance due to the presence of conchoidal fractures, it therefore breaks with very sharp edges. It is this particular feature which has made obsidian an important rock in human history and evolution and why it is so well known and popular, as the sharp edges allowed it to be used in the past in cutting and piercing tools, most notably, arrow and spear heads. It has been used experimentally as scalpel blades in the past and recent years. These particular samples come from South East Mexico, the pieces will display typical black colouration and conchoidal fractures, making them suitable for both collectors, enthusiasts and educational use. Each sample will 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.
Weight | 130 g |
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Specimen Size | 2" x 2", 3" x 2", 4" x 3", Thin Section Slide |
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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.
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
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
Peridotite, found in Finland, is a dense, coarse grained igneous rock. It is commonly used in saunas due to certain porpertie. These rock specimens are ideal teaching aids or collectors specimens. Supplied in a card tray with label, offered in 3 optional sizes.
We also supply Peridotite thin sections for microscope study which are available to buy HERE.
32 in stock
Amygdaloidal basalt is an igneous rock which is extrusive in nature, these specimens formed over 60 million years ago during the Tertiary period and come from Ireland. They are part of the Antrim lava group and exhibit a dark colouration with occurrences of amygdales containing quartz and calcite crystals. As a basalt they are somewhat dense, but lighter than pure samples due to the cavities within them which formed as a result of gaseous activity during their ejection. Over time, hydrothermal fluids pass through the rock and minerals form within the cavities, which gives the usually dark coloured rock a speckled appearance. These samples are available in various sizes and are suitable for higher educational use to detail the subtle differences between similar igneous rocks, they come supplied in a card tray with an information label.
59 in stock
Micro Granite is a variation of the granite group of rocks, composed of the minerals quartz, feldspar and mica. These particular samples were collected from Threlkeld quarry, Cumbria, UK. They are supplied in a small white tray with an information label.
We also supply Microgranite thin sections for microscope study which are available to buy HERE.
193 in stock
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
Diorite rock specimens from Cockermouth, Cumbria, is an intrusive igneous rock from the Ordovician period with a coarse, phaneratic texture composed of plagioclase feldspar, biotite mica as well as hornblende with intermediate chemistry. Found with the Skiddaw group, the rock samples are more suited for serious collectors and higher level education to describe the chemistry and mineralogy of various igneous groups. Available in 3 sizes and supplied in a card tray with an information label.
We also supply Diorite thin sections for microscope study which are available to buy HERE.
73 in stock
Pink granite rock specimens from China, containing the expected granite minerals, however, these specimens are higher in biotite mica, thus making the pieces seem darker than other pink granites.
86 in 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.
An igneous rock exhibiting a porphyritic texture containing large cubic crystals of feldspar within a fine grained matrix. Collected near Oslo, Norway. Each sample is supplied in a labelled card tray. Each sample is supplied in a labelled card tray.
We also supply Rhomb Porphyry thin sections for microscope study which are available to buy HERE.
45 in stock
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
Olivine dolerite igneous rock specimens from Clee Hill, Shropshire, UK, composed of pyroxene minerals such as augite and magnetite as well as plagioclase feldspar. The samples are fine grained and crystalline in texture with a dense weight and black colouration. Similar in appearance to gabbro and basalt, the rock samples are suitable for serious collectors or higher level education to explain the difference in chemistry and mineralogy of igneous rocks. The samples are available in three sizes and supplied in a card tray with an information label.
We also supply Olivine Dolerite thin sections for microscope study which are available to buy HERE.
62 in stock
Shap granite igneous rock specimens from Shap Fell, Cumbria, UK which exhibit typical coarse grained crystalline textures expected of intrusive felsic rocks, being composed of quartz, plagioclase and orthoclase feldspar and biotite mica. This popular granite is very sought after for a variety of applications and has a colourful appearance. It is believed to have formed during the early Devonian period as a plutonic intrusion in the area and is quarried extensively. Samples are ideal for collectors of all levels and ages as well as all educational levels as the minerals can be easily described with the origin and processes being suitable to teach higher level students. Samples are available in three sizes and come supplied in a card tray with an information label.
We also supply Shap Granite thin sections for microscope study which are available to buy HERE.
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
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