This is a 16 inch strand of polished semi-precious tiger eye round stone beads.

This stone is called tigers eye because the rock captures light inside itself and refracts it back out in mesmerizing bands of shimmering light that can capture the imagination into believing that a dangerous feline is looking at you from within.
These warm sensual beads are threaded on a temporary string for ease of use in making rock jewelry such as necklaces, earrings, rings, bracelets, or pendants.
To give you a sense of perspective the graph paper behind the rocks is calibrated at 1/4". The beads measure about 4.5 mm to 4.8 mm in diameter.