Dashington&reg; Bright Blue, 1 Pound Bag, Translucent Acrylic Gems, Ice Rocks, for Table Scatter, Vase Filler, Aquarium Decor Dashington High Quality Decorative Acrylic Ice Gems. This will sink when placed in water. They will not float. Item is bright blue but 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. 1 pound bag contains approximately 150 gems