A striking and rich specimen of sphalerite (var. cleophane) from the classic mining district of Trepça, Kosovo. The piece features dozens of well-formed, translucent to transparent crystals with a vivid greenish-yellow hue, known as cleophane — a rare, iron-poor variety of sphalerite prized for its color and clarity. The crystals are sharply defined with a glassy luster, densely covering the matrix in a highly aesthetic distribution. Under strong light, the cleophane crystals reveal internal glow and color zoning, giving the piece excellent display value. The white contrasting matrix enhances the brightness and definition of the green crystals, making it a beautiful and highly collectible example from one of Europe's most famous mining localities.