It is found at many localities amongst those which have yielded typical botryoidal specimens may be mentioned the Restormel iron mine at Lostwithiel in Cornwall, Brendon Hills in Somerset, Hoy in Orkney, Sayn near Coblenz, Hout Bay near Cape Town, and Crimora in Augusta county, Virginia. PSILOMELANE DENDRITE Psilomelane is a group name for hard black manganese oxides including hollandite and romanechite. It is a common and important ore of manganese, occurring under the same conditions and having the same commercial applications as pyrolusite.
PSILOMELANE DENDRITE PC
of Size 44.0 x 24.0 x 5.5 MM Approx., 1 Pc Gem has Opaque. The name, dating back to 1758, makes reference to its characteristic appearance, from the ancient Greek ψιλός: psilos for (naked, smooth, bald) and μέλας: melas (black) a Latinized form is calvonigrite from calvo for (bald, smooth) and negri (black). This 100 Natural 54.90 TCW Germany Psilomelane Dendrite Oval Cabochon Super Quality Gem by DVG. It is soluble in hydrochloric acid with evolution of chlorine gas. The mineral often contains admixed impurities, such as iron hydroxides. The streak is brownish black and the fracture smooth. Merlinite is also known as Dendritic Agate, Dendritic Opal, Psilomelane, and The Magic Bearer. The mineral is readily distinguished from other hydrous manganese oxides ( manganite and wad) by its greater hardness 5 to 6 the specific gravity varies from 3.7 to 4.7. Psilomelane has no definite chemical composition and occurs as botryoidal and stalactitic masses with a smooth shining surface and submetallic lustre. The amount of manganese present corresponds to 70-80% of manganous oxide with 10-15% of available oxygen.
PSILOMELANE DENDRITE PLUS
Original price: 48 IG Sale Price: 34 plus free shipping in the US Comment SOLD and. It is sometimes considered to be a hydrous manganese manganate, but of doubtful composition. SALE German Psilomelane Dendrite Necklace with Abalone Accent. Generalized formula may be represented as Ba(Mn 2+)(Mn 4+) 8O 16(OH) 4 or as (Ba,H 2O) 2Mn 5O 10. Psilomelane is erroneously, and uncommonly, known as black hematite, despite not being related to true hematite, which is an iron oxide. Psilomelane consists of hydrous manganese oxide with variable amounts of barium and potassium. Psilomelane is a group name for hard black manganese oxides including hollandite and romanechite. Hard black manganese oxides such as hollandite and romanechite ( February 2023) ( Learn how and when to remove this template message)īa(Mn 2+)(Mn 4+) 8O 16(OH) 4, or as (Ba,H 2O) 2Mn 5O 10
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