10% of the flower drying sand is orange humidity indicating silica crystals and is 90% clear silica beads;. Includes: 3 LBS silica gel flower drying; airtight container; soft brush ; spatula ;. Reusable: Silicone can be placed in an oven at 200-250F for 0.5-2 hours or in a microwave oven under defrosting conditions for about 10-30 minutes or until all green crystals turn orange again; Do not use temperatures exceeding 250 degrees Fahrenheit in the oven.