Aquamarine

Hardness: 7.5-8 on the Mohs scale. Color: Typically light blue to bluish-green, often with a vitreous (glassy) luster. Crystal Structure: Hexagonal system, often forming prismatic crystals. Cleavage: Indistinct basal cleavage. Specific Gravity: 2.7-2.8.

Aquamarine forms in pegmatites, which are igneous rocks that form from the slow crystallization of magma. It is typically found in coarse-grained igneous rocks and metamorphic rocks such as schists. Its characteristic blue color is due to the presence of iron impurities within the beryl crystal structure. Geological age varies depending on the specific deposit, but it is often found in geological settings associated with mountain-building events.

Primarily used as a gemstone in jewelry due to its beautiful blue color and good hardness. It is fashioned into various cuts for rings, necklaces, earrings, and bracelets. Larger, clearer specimens are highly valued.

Aquamarine is the birthstone for March. Its name comes from the Latin words 'aqua marina,' meaning 'water of the sea,' a reference to its ocean-like color. Historically, sailors believed aquamarine would protect them at sea and prevent seasickness. The largest aquamarine ever found was in Brazil in 1910, weighing 110 kg and measuring 48.5 cm long, yielding over 200,000 carats of cut stones.

Aquamarine can be identified in the field by its characteristic pale blue to bluish-green color, its hexagonal crystal habit (when well-formed), and its relative hardness. It is commonly found in Brazil (Minas Gerais), Pakistan, Nigeria, Madagascar, Zambia, Mozambique, the United States (Colorado), and Afghanistan. When identifying, look for clear to translucent crystals with a distinctive blue hue. Distinguish from similar-looking stones like blue topaz by testing hardness (topaz is 8, aquamarine 7.5-8) and by the crystalline structure.