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PRODUCTS BY WEIGHT
BOX SETS
PLASTIC DISPLAY PRODUCTS
PRODUCTS BY WEIGHT
BOX SETS
PLASTIC DISPLAY PRODUCTS
£8.00 ex VAT
Chert, a hard cryptocrystalline silica found as nodules & bands within the Cretaceous Chalk. Supplied by weight in 1 kilo bags.
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
Chert is a hard, cryptocrystalline silica of sedimentary origin. It is often to be found as nodules & irregular masses within sedimentary rocks. It is specifically associated with chalk & marly limestones. They can be found in variety of colours from dark grey-black, brown, green through to yellow & white. Often with a white, rough textured outer layer. Supplied in lots of 1 kilogram in a polythene bag with data label, size of pieces may vary.
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Chert is classified as a sedimentary rock and is a hard cryptocrystalline form of silica. It is found as nodules and bands within the Cretaceous Chalk, with these samples coming from Norfolk in the UK. It is well known for its glassy crystalline texture which allows pieces to be knapped and for this, the rock was used by stone age humans to make various cutting tools and weapons as it often break, leaving sharp edges. The specimens exhibit an earthy brown colour with a waxy lustre and are available in various sizes, which will come supplied in a card tray with an information label.
30 in stock
Chalk is a fine, porous, white form of limestone of Cretaceous age. Formed from the accumulation of coccoliths in a relatively deep marine environment. Supplied by weight, sizes vary.
73 in stock
Limestone, a common sedimentary rock often used in building and stone work. These samples are carboniferous in age and are supplied by weight in lots of 1 kg.
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.
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 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
Graphic Granite is a leucocratic igneous rock found predominantly in granitic pegmatites. It’s coarse intergrowths of feldspars display a Runic or Cuneiform configuration hence the term “graphic”
98 in stock
Microgranite thin section slide exhibiting the medium grained nature of this intrusive igneous rock. The crystals in microgranite are smaller than those of normal granite indicating that it cooled at a quicker rate.
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
Metagabbro specimens from Lom, Central Norway. Also known as scapolite-hornblende due to the absence of feldspar in the rock are available in 3 optional sizes and come supplied in a card tray with a data label.
40 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
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.
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.
Pink Granite, rich in potassium feldspars giving the distinctive pink hue, easily identifiable as a granite due to its mineral composition. Specimens come from Scotland and are supplied in a card tray with label.
8 in stock
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.
Granite adamellite thin section slide exhibiting crystals of quartz, biotite and feldspar. We collected this material from the famous Shap Fell quarry, in Cumbria hence the rocks alternative name ‘ Shap Granite ‘.
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.
8 in stock
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.
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