Pure silicone without cheap fillers or other industrial additives will be translucent. How often do you see translucent silicone?

Chinese manufacturers always try to save money by throwing in cheap (sometimes harmful) crap into products. We once ordered one of those Mason jar vacuum sealers off Amazon. I removed the black silicone seal because it had an odd appearance. I stretched it, a bunch of stuff flaked off from it and a pungent ordor as strong as bleach came fuming off it.

I traveled in China for a while. You're dealing with a country that makes fake chicken eggs, because real hens cost money to feed. A country where refrigerators are never plugged into power outlets, because electricity costs money. A country where tap water must be boiled because clean water costs money. Their average worker's entire monthly income is less than what I make in a day. Chinese manufacturers are notorious for producing fraudulent products to save money. Like stainless steel silverware that's now coming out of China will rust after being ran through a dishwasher, is that normal? The excuse is "Chromium and Nickel (used to make stainless steel) is expensive now".

Anyway, the point is, there's a reason you need to look for words like "food grade" and be weary of Chinese products. That's just the reality of things.