1) try elasticity
Rubber, latex elasticity is better, silicone is more fragile, in the selection, you can try the elasticity, if the elasticity is very good, it is possible that the rubber; if the elasticity is not very good, it is possible that the silicone.
2) Look at the color
Rubber, latex due to the content of impurities, can not do transparent color products, while silicone is colorless and transparent, to do transparent silicone rubber products must be raw materials with silicone.
3) smell
Rubber, latex products taste stronger, smell will smell pungent, some manufacturers in order to cover up the flavor and increase the aroma, so the choice of silicone raw materials will be much better.