The topic of Clintonite is one that has generated interest and debate over time. Whether due to its impact on our lives, its historical relevance or its influence on society, Clintonite has been the object of reflection and study. In this article, we will explore different aspects related to Clintonite, from its origins to its evolution today. We will analyze its importance in different contexts and how it has marked the public agenda. Additionally, we will examine opinions and perceptions about Clintonite and how it has shaped the way we relate to the world around us. Using a multidisciplinary approach, we will seek to shed light on this fascinating and often complex topic, with the goal of providing a deeper and broader understanding of Clintonite.
Clintonite | |
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![]() Clintonite with spinel on orthoclase matrix from Amity, New York (size: 9.3 × 5.7 × 3.8 cm) | |
General | |
Category | Phyllosilicate mica group |
Formula (repeating unit) | Ca(Mg,Al) 3(Al 3Si)O 10(OH) 2 |
IMA symbol | Cln |
Crystal system | Monoclinic |
Crystal class | Prismatic (2/m) or domatic (m) |
Space group | C2/m or (?) |
Unit cell | a = 5.204 Å, b = 9.026 Å, c = 9.812 Å; β = 100.35°; Z = 2 |
Identification | |
Color | Colorless, yellow, orange, red-brown, brown, green |
Crystal habit | Tabular pseudohexagonal crystals; foliated or lamellar radiated; massive |
Twinning | Spiral polysynthetic twinning |
Cleavage | Perfect on {001} |
Tenacity | Brittle |
Mohs scale hardness | 3.5 on {001}, 6 at angle to {001} |
Luster | Vitreous, pearly, submetallic |
Streak | White, slightly yellow-gray |
Diaphaneity | Transparent to translucent |
Specific gravity | 3.0–3.1 |
Optical properties | Biaxial (−) |
Refractive index | nα = 1.643 – 1.648 nβ = 1.655 – 1.662 nγ = 1.655 – 1.663 |
Birefringence | δ = 0.012 – 0.015 |
Pleochroism | X = colorless, pale orange, red-brown; Y = Z = pale brownish yellow, pale green |
2V angle | Measured: 2° to 40° |
References |
Clintonite is a calcium magnesium aluminium phyllosilicate mineral. It is a member of the margarite group of micas and the subgroup often referred to as the "brittle" micas. Clintonite has the chemical formula Ca(Mg,Al)
3(Al
3Si)O
10(OH)
2. Like other micas and chlorites, clintonite is monoclinic in crystal form and has a perfect basal cleavage parallel to the flat surface of the plates or scales. The Mohs hardness of clintonite is 6.5, and the specific gravity is 3.0 to 3.1. It occurs as variably colored, colorless, green, yellow, red, to reddish-brown masses and radial clusters.
The brittle micas differ chemically from the micas in containing less silica and no alkalis, and from the chlorites in containing much less water; in many respects, they are intermediate between the micas and chlorites. Clintonite and its iron-rich variety xanthophyllite are sometimes considered the calcium analogues of the phlogopites.
Typical formation environment is in serpentinized dolomitic limestone and contact metamorphosed skarns. It occurs with talc, spinel, grossular, vesuvianite, clinopyroxene, monticellite, chondrodite, phlogopite, chlorite, quartz, calcite and dolomite.
Clintonite was first described in 1843 for an occurrence in Orange County, New York. It was named for De Witt Clinton (1769–1828).