Aquamarine and Muscovite

ID	132
Mineral	Aquamarine Muscovite
Location	Gilgit-Baltistan - Pakistan
Fluorescence	LW-UV: close SW-UV: close
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Mindat data

ID	289
Long ID	1:1:289:1
IMA Status	0 1
Variety of	819
Entry type	2
Description	A sky-blue to sea-green gem variety of beryl. It is mainly associated with granitic pegmatites.
Other Occurrences	pegmatites
Cleavage	Imperfect
Colour	Blue
Hardness (min)	7.5
Hardness (max)	8.0
Luminescence	Non-fluorescent
Lustre	Vitreous
About the name	The name aquamarine comes from aqua (Latin for 'water'), and marine, deriving from marina (Latin for 'of the sea'). The first reference in English to "Aquamarina" appears in Anselmus Boetius De Boot book GEMMARUM ET LAPIDUM HISTORIA (1609, in Latin). It was later cited in "A Lapidary History or History of Precious Stones" by Thomas Nicols, Cambridge (1652, page 114), where it states that the name was used by the Italians for blue-green varieties of beryl.
Streak	White
Crystal System	Hexagonal
key_elements	0

ID	2815
Long ID	1:1:2815:4
Formula	`KAl₂(Si₃Al)O₁₀(OH)₂`
IMA Status	0 1
Other Occurrences	Muscovite is common in many different rock types as a primary mineral.
Diapheny	Transparent,Translucent
Cleavage	Perfect on {001}.
Tenacity	elastic
Colour	White to colorless, silvery-white, and tinged various colors by impurities.
Hardness (min)	2.5
Hardness (max)	2.5
About the name	The earliest names attributable to muscovite include Muscovy Glass, Cat Silver, and Lapis Specularis (stone mirror); these names appearing in texts in the seventeenth century and before. The stand-alone name 'Muscovite' was used as early as 1794 by Johann Gottfried Schmeisser in his System of Mineralogy and is derived from the term "Muscovy glass," which was in common use by that time. Muscovy Province in Russia yielded sheet mica for a variety of uses. Muscovite and sometimes similar species were earlier called mica (Phillips and Kersey, 1706), glimmer (Phillips and Kersey, 1706), and isinglass (1747 according to OED) but all of these terms are still in use to some degree. It should be noted that mica, glimmer, and isinglass were also used for a variety of materials before these given dates and in those earlier times did not always indicate what would be a mineral, much less muscovite proper. Isinglass, for example, was originally used for a gelatinous bladder found in sturgeon.
Streak	White
Crystal System	Monoclinic
Cleavage Type	Perfect
Fracture type	Micaceous
Morphology	Crystals uncommon, tabular {001} with rhombic to hexagonal outlines, often bound by {221}, {_111} and {010} (hkl refer to -2M^1 polytype). Less common as prismatic, parallel to [001], with a crude hexagonal cross section. Most typically found as "books" and as flaky grains in various rocks. Sometimes in plumose or fibrous aggregates.
Twinning	Mica law twins common [310] forming six pointed stars, less common with the composition plane perpendicular to {001} (hkl refer to -2M^1 polytype).
shortcode_ima	Ms
Group	Dioctahedral mica

Price: € 125

Dimensions: Not registered

Weight: 33 g

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Notes:

Symbol	Element
Al	Aluminium
Be	Beryllium
H	Hydrogen
K	Potassium
O	Oxygen
Si	Silicium

Aquamarine and Muscovite

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