How to tell if my cheap sunglasses are made of glass?

[Herriman]

Lately I bought some cheap sunglasses which should be made of glass, but I find it just like other sunglasses which are made of plastic. I don't know how I can tell if they are glass or plastic.Can someone help me ?

[Herrin]

At room temperature, glass is a little colder than the room temperature while plastic is the same as the room temperature. You can use your cheek to touch the glass and plastic, the one you feel much cooler is glass. Hope this helps . You can try this by yourself. It's a easy way to tell them apart.

[Herrings]

First of all, check the weight of your glasses. Glass lenses are usually heavy while plastic lenses are lighter. Then you can let the glasses lens touch your cheek. If you feel much cool, then they are made of glass. If you feel room temperature, then they are made of plastic. Plastic lenses are easy to get scratched while glass lenses are not.