出典:Wiktionary
出典:『Wiktionary』 (2026/08/17 01:39 UTC 版)
arfvedsonite (countable and uncountable, plural arfvedsonites)
出典:Wikipedia
出典:『Wikipedia』 (2011/05/22 06:32 UTC 版)
Arfvedsonite is a sodium amphibole mineral with composition: [Na][Na2][(Fe2+)4Fe3+][(OH)2|Si8O22]. It crystallizes in the monoclinic prismatic crystal system and typically occurs as greenish black to bluish grey fibrous to radiating or stellate prisms. It has a specific gravity of 3.44 to 3.45 and a Mohs hardness of 5.5 to 6. Refractive indices are nα=1.652 - 1.699, nβ=1.660 - 1.705, and nγ=1.666 - 1.708.