I'm not an engineer or a chemist, so please do take all of this with a grain of salt.

I believe that platinum curing refers to silicone's finishing process - the process that allows a toy made from silicone to keep its shape and ensures that all the little silicone molecules stay happy.

According to the good people at Dow Corning, silicone can be cured using peroxide or platinum cure mechanisms. Peroxide curing has a bunch of good things going for it, but the final product tends to have imperfections in its appearance. Platinum curing has its own set of plusses and minuses as well.

The first lesson here is that the "100% platinum cured" business is marketing nonsense. There's nothing more or less fabulous about platinum curing than there is about anything else. It's just a chemical reaction that gives silicone certain properties.

TPR is thermoplastic rubber. It's in the same chemical family as silicone is, but it has very different properties. It's also cured differently. To the best of my knowledge (again a reminder to take this with a grain of salt), platinum curing isn't used on TPR.

Long story short, my best guess is that if it's platinum cured, it's silicone.

If you're thinking about how porous the toy may be, though... wouldn't it make sense to err on the side of caution and just use a condom?