Madstones rhymes with:
gladstones, gladstones, headstones, redstone's, blackstone's, bridgestone's, cherrystones, cobblestones, cornerstones, firestone's, flagstones, folkstone's, gallstones, gemstones, gladstones, gravestones, hailstones, headstones, keystone's, keystones, limestones, livingstone's, milestones, moonstones, redstone's, rhinestones, tombstones, waterstone's, yellowstone's
Madstones sounds like:
medicating, medications, mitigating