In defense of the cost of the Willmann -Bell Kits, note that you receive two pyrex blanks, either of which you can use for a mirror. I recommend that when you get the kit you make a cement (or plaster) tool, and glue ceramic tiles to it. Use this for grinding. At the end of grinding, make a second tool for your pitch lap. When you are done, sell the other blank, the two tools, and the left over abrasive to a friend at half the cost of the original kit. You may need to acquire a little more abrasives. Basically, you can make two mirrors for the price of the one kit. Most other suppliers either supply one pyrex blank, and a plate glass tool, or a ceramic tool. These are less suitable or useless as a mirror. .....RICH