Inosilicates Gallery

Inosilcates are called the chain silicates and are composed of two classes, the single chain and double chain silicates.

The single chain silicates have SiO₄ tetrahedrons which share two oxygens with two other tetrahedrons forming  a virtually endless chain. This makes for a ratio of silicon to oxygen of 1:3. The tetrahedrons alternate to the left and to the right of the axis formed by the linked oxygens. More complex chains can form a spiral. In cross section, the chain forms a trapezoid. It is this shape which produces the angles between the faces of the crystals and the directions of cleavage.

 The double chain silicates have  two single chains which lie next to each other. An oxygen ion links each of the right sided tetrahedrons in the left chain with the left sided tetrahedrons in the right chain. Because there is an extra shared oxygen for every four silicons,  the ratio of silicon to oxygen is reduced to 4:11. The double chain is a chain of six sided rings. It has a similar cross section to a single chain, except the trapezoid is longer, which produces a different set of angles.

The cleavage of the chain silicates occurss between the chains; the chains are not broken. This produces a prismatic cleavage. For single chained silicates, the two directions of cleavage are close to 90 degrees which forms almost square cross sections. For double chain silicates, the cleavage angle is close to 120 and 60 degrees which forms rhombic cross sections.

Single chain silicates: Neptunite, Okenite, Pectolite, The Pyroxene group (Aegerine, Augite, Diopside, Spodumne (Kunzite, Hiddenite), Jadeite and others), Rhodonite, Serandite, Shattuckite, and others

Double chain silicates: Amphibole group (Actinolite, Edenite, Cummingtonite, Hornblende, Tremolite, Richterite, Glaucophane and others), Astrophyllite, Babingtonite, Charoite, Inesite, Plancheite and others

minerals in alphabetical order by first letter only

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