Since Priority Mail includes insurance, I ship all glassware, dinnerware, and pottery via Priority Mail.  I do pack with plenty of shipping peanuts and bubble wrap but want to make sure your package is covered for loss or damage. 

I have more than twenty years Ebay selling experience, combine shipping, and ship the day following receipt of payment or same day if payment is received before 9 AM eastern.  

Good luck and happy Ebay shopping.