Green Aventurine Gemstone Round Smooth 8 mm 33 Beads Islamic Religion Tasbih for Muslim Prayer Men Women Chain (Color : Green)To keep track of counting either the phalanges of the right hand or a misbaha is used. The term tasbeeh is based on 3 root letters Agate is formed by the deposition of silica in gas cavities in lava, which results in the distinctive bands or stripes we see in the stone. They come in varied shades of red, orange, and brown, Black which often alternate with striking bands of white.