Moroccan Star Aragonite
These distinctive clusters are a fascinating example of a geological phenomenon called cyclic twinning. While many crystals grow in a single direction, Aragonite has a habit of growing outward from a central point in multiple directions at once. This creates the hexagonal, "starburst" shapes that give this stone its name.
 
Looking closely at the structure, you’ll see radiating "twinned" crystals that intersect each other. Geologically, Aragonite is a polymorph of calcium carbonate—meaning it has the exact same chemical ingredients as calcite, but a completely different internal structure. Because it formed under specific temperature and pressure conditions, the atoms arranged themselves into these dense, orthorhombic prisms rather than the rhombohedrons you’d see in a piece of common calcite.
 
The warm, honey-to-brick-red hues are caused by trace amounts of iron oxide present during the crystallization process. These pieces are often found in the weathered clay and soil of Morocco, where the surrounding earth protected the delicate, radiating arms of the "stars" until they were uncovered.
 
Geological Profile
The "Star" Effect: Known as a pseudo-hexagonal shape. While the individual crystals are orthorhombic, they twin at 120 degree angles to trick the eye into seeing a six-sided star.
Composition: A carbonate mineral that is naturally more soluble and denser than its "cousin," Calcite.
Surface Texture: These pieces often have a matte, earthy luster with translucent tips that catch the light, highlighting the termination of each individual crystal arm.