resin casting

but they are reusable and you can add clean water to them to refresh them

and even featured in components of the Hubble Space Telescope

etc -PLASTIC CRAFT SNOWFLAKES: These white snowflakes are absolutely ideal for art craft project like decorating Christmas card

Spenco Gel Comfort Shoe Insole with Cushioning and Support, Rocks for Crafts resin castingSpenco Gel Comfort Shoe Insole with Cushioning and Support, Triple density replacement shoe insole provides cushioning and support for comfort and arch support. Provides lasting comfort and shock absorbtion when standing for long periods of time. Recommended for daily wear in casual, work or walking shoes. Extra cushioining with a softer gel pod in the heel to absorb impact at heel strike.