Description of Lapidary Equipment. MK1503. Lapidary Kit. Barranca Diamond Wet Polishing Kit for Rock. The MK1503 Wet Polishing Lapidary Kit is ideal for handheld grinding and polishing of gemstone and rock materials such as onyx, agate, petrified wood, jade, opal, etc. The polisher is used with the vacuum brazed convex wheel for ...