Making Cabs out of Zeolites

I decided to get some of the Zeolites found here in the deccan traps polished into cabs and I got mixed results. Some minerals, such as in Stilbite, was impossible to find a good hard rough, the ones I had were small pieces of Stilbites, all looking very brittle, they hadn't seen many moons or the hard sun. These are mainly from Jalgaon, but are found throughout the western to mid and southern parts of India.
Finally, only 2 ovals could be salvaged, none of them looking too pretty, but I've added a photo just for the record.