What are the best Materials for making coasters?

Well, that's horses for courses, really, isn't it?

A coaster in itself is a pretty simple thing, just provide a barrier between the bottom of the cup and the table it's on. 

Anything can be a coaster, glass, slate, ceramic, wood, bamboo.. the list is endless. So there is no best, not really, it's all personal taste, as long as it functions, then it's the best.

So, I thought a lot about this, there is practically an unlimited range of materials to print on, and each have there pros and cons, and some limit you in other ways. 

What I did as Modmat was look for an effective high ground, the image itself to me is the most important, i want it to be bright, distinct and vibrant with good contrasts and a strong base white coat. That's the goal, to show off my work to the best of its ability 

So since my mousemats and slipmats are all sublimated works, then i naturally I produce sublimated coasters for the maximum depth of colours on a very high-quality MDF board blank.  That allows me to keep the costs down,for the sets and to keep the quality up and make the process of creation fast and efficient.