RARE CAVANSITE STILBITE Crystal Cluster Mineral Specimen Poona INDIA

Description: This specimen weighs 0.66 grams. It measures 13 mm x 10 mm x 9 mm. I offer a shipping discount for customers who combine their payments for multiple purchases into one payment! The discount is regular shipping price for the first item and just 50 cents for each additional item! To be sure you get your shipping discount just make sure all the items you want to purchase are in your cart. Auctions you win are added to your cart automatically. For any "buy it now" items or second chance offers, be sure to click the "add to cart" button, NOT the "buy it now" button. Once all of your items are in your cart just pay for them from your cart and the combined shipping discount should be applied automatically. I offer a money back guarantee on every item I sell. If you are not 100% happy with your purchase just send me a message to let me know and I will buy back the item for your full purchase price. Hi there. I am selling this really lovely cavansite and stilbite mineral specimen. It is from Poona India, or it may be spelled Puna, India. If you have any questions, do not hesitate to ask me. Have fun bidding, thanks so much for visiting my auction and have a great day! The following is a wikipedia entry about cavansite: CavansiteFrom Wikipedia, the free encyclopediaCavansiteGeneralCategory Silicate mineralFormula(repeating unit) Ca(VO)Si4O10·4(H2O)Crystal system OrthorhombicCrystal class Dipyramidal (mmm)H–M Symbol: (2/m 2/m 2/m)Space group PcmnUnit cell a = 9.792(2) Å,b = 13.644(3) Å,c = 9.629(2) Å; Z = 4IdentificationColor Brilliant sky-blue to greenish blueCrystal habit Radiating acicular prismatic crystals commonly as spherulitic rosettesCleavage Good on {010}Tenacity BrittleMohs scale hardness 3 - 4Luster Vitreous, pearlyStreak Bluish-whiteDiaphaneity TransparentSpecific gravity 2.25 - 2.33Optical properties Biaxial (+)Refractive index nα = 1.542(2) nβ = 1.544(2) nγ = 1.551(2)Birefringence δ = 0.009Pleochroism Visible: X=Z= colorless Y= blue2V angle Measured: 52°References [1][2][3][4]Cavansite, whose name is derived from its chemical composition, calcium vanadium silicate, is a deep blue hydrous calcium vanadium phyllosilicate mineral, occurring as a secondary mineral in basaltic and andesitic rocks along with a variety of zeolite minerals. Discovered in 1967 in Malheur County, Oregon, cavansite is a relatively rare mineral. It is polymorphic with the even rarer mineral, pentagonite. It is most frequently found in Pune, India and in the Deccan Traps, a large igneous province. Contents [hide] 1 Uses of cavansite2 Associated minerals3 Notes for identification4 ReferencesUses of cavansite[edit]While cavansite does contain vanadium, and could thus be a possible ore source for the element, it is not generally considered an ore mineral. However, because of its rich color and relative rarity, cavansite is a sought after collector's mineral. Associated minerals[edit] Cavansite on stilbite from the type localityMembers of the apophyllite groupMembers of the zeolite group, particularly stilbite.babingtonite, Ca2Fe2Si5O14OHquartz, SiO2calcite, CaCO3pentagonite, Ca(VO)Si4O10 · 4(H2O)Notes for identification[edit] Stalactitic cavansite, 3.6 x 2.1 x 1.8 cm, Wagholi, Pune District, Maharashtra, IndiaCavansite is a distinctive mineral. It tends to form crystal aggregates, generally in the form of balls, up to a couple centimeters in size. Sometimes the balls are coarse enough to allow the individual crystals to be seen. Rarely, cavansite forms bowtie shaped aggregates. The color of cavansite is distinctive, almost always a rich, bright blue. The color is the same as its dimorph, pentagonite, but the latter is generally much more spikey with bladed crystals. Finally, the associated minerals are useful for identification, as cavansite is frequently found sitting atop a matrix of zeolites or apophyllites.

Price: 39.99 USD

Location: Tucson, Arizona

End Time: 2024-11-24T21:45:13.000Z

Shipping Cost: 5.95 USD