Guardian Ware began as Silver Seal back in the mid 1930's and was manufactured in their own factory here in southern California. My Grandmother on my father's side was given a number of Silver Seal pieces as a wedding gift in 1934. Both Guardian Ware and Silver Seal can be found regularly on eBay, but I've never seen a piece turn up that wasn't in desperate need of a good polishing. When properly done the textured body of the pieces will glitter brightly while the flat border areas will take on a mirror shine. They really do look impressive this way, especially when sitting on a white table cloth. If I recall what I've read in the past correctly their factory burned down in the early fifties and brought production to an end, but so many pieces were sold that anyone that wants a complete set will have little trouble putting one together off of eBay alone. I have a number of them that I use myself, including my grandmothers old Silver Seal roaster that makes an outstanding pot roast.