Replacement Sand, set is a refill of the sand included with the Tectonics model. Set includes one pound each of beige, black, blue, orange and yellow sand
Minerals Model Set, Build the most abundant silicate minerals including feldspar, quartz, olivine, pyroxenes, amphiboles, micas, clay minerals, Students Learn how models of silicate minerals are related to unit cell/crystal lattice structures, It has enough parts to construct