Aragonite is a naturally occurring mineral composed of calcium carbonate with the chemical formula CaCO₃. It belongs to the carbonate mineral group and is one of the two main polymorphs of calcium carbonate, the other being calcite. Aragonite crystallizes in the orthorhombic crystal system and is known for its distinctive crystal habits, often forming needle-like, fibrous, or columnar structures. The mineral is typically found in colors such as white, colorless, brown, yellow, orange, and reddish hues. Some varieties may also show green or blue shades due to impurities. Aragonite has a vitreous to resinous luster and is usually translucent to opaque, though transparent crystals are rare. Its unique formations, such as star-like clusters and branching patterns, make it highly attractive for collectors.