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"I cannot recommend Keith and KSC Crystals highly enough! He goes to great lengths to source the very best quality crystals which he sells at the very best prices. He is knowledgeable and enthusiastic and he has an obvious love of the mineral kingdom - this is seen in every aspect of the service which he provides. Keith also runs the Crystal Healing Diploma course, this was also an amazing experince. Even though I live on the East Coast of the UK and work in Nottingham (which means lots of travel), I still order from Keith in Manchester because of his passion, the quality of his crystals and the level of service that he provides. You can rely on him to choose crystals for you, so there is no need to visit him if travel is a problem. (even though there is a crystal shop in my town, I still choose to shop at KSC Crystals!) Also, not everything that he has in stock is on the website yet, so you can always call him if you are looking for something in particular. What more can i say? If you love crystals, you will love KSC Crystals. 

Jane Rapin

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Seraphinite 4
Seraphinite 4
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Proetida Trilobite Fossil

Price: £19.00
Product Description

Proetida Trilobite

Meighs 36.6 Grams

Measures 35mm x 15 in total

Proetida is an order of trilobite that lived from the Ordovician to the Permian. It was the last order of trilobite to go extinct, finally dying out in the Permian extinction.
These typically small trilobites resemble those of the order Ptychopariida, from which the new order Proetida was only recently separated in 1975 by Fortey and Owens. Like the order Phacopida, the proetids have exoskeletons  that sometime have pits or small tubercles, especially on the galbella  (middle portion of the head). Because of their resemblance to the Ptychopariida in some features, the proetids are included in the subclass Librostoma.
Unlike some trilobites of the order Phacopida, whose eyes  are schizochroal, the proetids have the more common Holochroal eyes. These eyes are characterized by close packing of biconvex lenses beneath a single corneal layer that covers all of the lenses. Each lens is generally hexagonal in outline and in direct contact with the others. They range in number from one to more than 15,000 per eye. Eyes are usually large, and because the individual lenses are hard to make out, they look smooth and sometimes bead-like.
The thorax of proetids was made up of anywhere between 8-22 segments, but most commonly 10. Many also have genal spines coming off either side of the head, though in some they are blunted. These two features can aid in distinguishing proetids from some trilobites in the order Phacopida, to which they can be very similar.
 

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