Although the glass paint I use states that the glassware should be dishwasher proof after firing, I have had poor experiences with the process.
I strongly recommend "HAND WASH ONLY" for the glassware.
Through my personal experience and those of my collector's, the glassware will last the life of the glass with hand washing.
All glassware orders come with care instructions.
If this did not fully answer your question than please contact Katherine and a response will be sent to you immediately (with in 24 hours)