To think of the number of Pyrex mixing bowls in kitchens across America, or possibly the world… are collectible items. Pyrex had (has) a good method for making an item more collectible by changing colors and themes that can easily (in most cases) be attributed to a time span of manufacture. In this case, my by orange Butterfly Gold bowl
was manufactured between 1979 – 1981. How did I find this information out? Thanks to the vast knowledge shared on the internet; focused collectors are able to share their knowledge garnered from books, catalogs, conventions, work history, articles, interviews and so many other means…now accessible to us all, if they feel inclined to share.