Dashington 3 Pounds - Purple Translucent Acrylic Gems, Ice Rocks, for Table Scatter, Vase Filler, Aquarium Decor, Bulk Amount. Dashington High Quality Decorative Acrylic Ice Gems. This will sink when placed in water. They will not float. Item is completely transparent. Light will shine through them. Each gem measures approximately 1". Made of acrylic - Acrylic is a clear high grade plastic. Commonly used for filler in vases for centerpieces or home decor. Use for aquarium decor. These will sink to the bottom of the tank. Spread these on the table for table scatter at your next event or dinner gathering. 3 pounds contains approximately 450 individual gems. Will cover approximately 195 Square inches.