Are these borosilicate glass or soda lime glass?
648310
I have no idea. They say Made in Korea. Microwave safe, oven safe, not stove top safe. I like them, they work for me.
1392443
I looked it up on the internet. They no longer used borosilicate. They now use tempered glass.
540469
I don't know. They were heavy and nice. It was just that the mold wasn't good so you could tell where they put the halves of the glass together. This was several years ago. They could have changed. Thanks
1561969
If I were to guess I would say no, it's probably made of soda-lime glass because it is cheaper to produce than borosilicate.
2112318
No they're not. When you're brewing Kombucha, the temperature change wouldn't be sufficient to crack regular glass, so borosilicate glass isn't necessary.
2207912
http://en.wikipedia.org/wiki/Borosilicate_glassAccording to Wikipedia, Pyrex kitchenware made in the US is made from soda lime.
495068
actual glass! they are very cool! I see the other responses, haha! I thought they were glass!
969572
They are glass - I have used them for years as everyday glasses. Just the right size.
1862645
Borosilicate glass is the hardest glass available and lead free. Pyrex products are made from borosilicate glass. Ozeri glasses are from China.
2126738
They are glass, I don't think they are real crystal. The fixture is awesome, doesn't look cheap, great buy for the price!
839243
They are glass, very sturdy & heavy. I love mine and bought 2 more after my first purchase.
1338206
REALITY CHECK... Borosilicate glass is laboratory grade, with a lower expansion coefficient than soda-lime glass (U.S. "Pyrex"). Borosilicate glass functions fine over a bunsen burner which can reach 2,200 deg. F. Hence, a filled borosilicate glass vessel will function just fine on an average stove top. Soda-Lime glass is typical for consumer grade "Pyrex" brand glass in the U.S., and the expansion coefficient is excessive for use on a traditional stovetop by a layperson. That means, a layperson using a stovetop will not understand how to minimize thermal gradient to prevent cracking. For those of you who do not accept and understand the physical reality of science, you can ameliorate your doubt by: (1) never using a "tea light" warmer which places your teapot directly above a concentrated open flame; and (2) placing a heat spreader between your teapot and heat source (e.g., a thick and flat sheet of aluminum). ... Please elect politicians who support public science education!
624549
they are glass. but they are made to withstand high temperature (inside a pressure cooker) so they might work for your needs. use at your own risk ;)
674006
They are not crystal, but are very break-resistant due to being made with titanium. We use them for red and white wine. They are sort of a universal shape. We love these glasses!
1234346
I had one shatter on me (it was more like 'exploded' than shattered) and I switched to the true borosilicate glass. In fact I got my borosilicate cookware from Amazon. Look for the Marinex brand.
1030073
Hi, they are not glass but a heavy plastic. I haven't had any trouble with mine. I use it almost every day and truly love it!
915445
they are glass and they are good to my opinion. You just have to remove sticker gently.