Discover the strength of obsidian with our Black Obsidian Tumble Stones . Obsidian is believed to encourage strength, integrity and grounding. Each tumblestone has been tumble polished, a process that smoothes and polishes the crystal to reveal its unique colour and form. Tumble stones are a wonderful way to enjoy crystals, whether for their beauty or healing powers. Our tumblestones make an ideal healing crystal - the perfect size to hold, place on the body or carry with you. They make great gifts and we have a wide range of inexpensive tumbled stones to add to your crystal collection or bring a little natural beauty into your home.