Step 1: Gathering Materials
You want to find a stone with a roughly triangular shape, and a disirable color. I'm not going to tell you where to find stones because that would be insulting. Everyone should know where to find at least one stone or rock.
Your going to need a way to shape the stones. I recommend a 4" angle grinder with a diamond coated sawblade attachment. Most people who aren't familiar with tools are saying, "whaaa?" so I'll explain what they are and where to get them.
4" angle grinder
This is a tool used to grind metal, hence the "girnder" part of the name. It is designed to spin at the appropriate RPM (revolutions per minute) with a 4" blade or grinding wheel, hence the "4"" in the name. the "angle" bit isn't important. Youcan find these at any hardware store, such as home depot (I got mine at Harbor Freight). It'll probably cost about 30$ (U.S. dollars)
Diamond coated sawblade
This is a sawblade designed to cut/grind through glass and stone. The cutting edge is lightly coated with crushed diamonds. I use a drycut one in this Instructable. Again you can find this in almostany hardware store, such as home depot (again I got mine at Harbor Frieght). Expect to pay abou 15$ (U.S. dollars)
Step 2: Forming the "V" of the Heart
To form the "V" of the heart, simply grind away the unwanted parts. It may take some practice, so be sure to gather a few rocks.
Step 3: Forming the "m" of the Heart
Simply grind away the unwanted parts, just like you did with the "V" of the heart. you may want to practice on junk stones before hand.
Step 4: Finishing
NOTE: I realized that when the stone heart got wet, it looked like it had been polished. Knowing that, I decided to oil it. I couldn't use just any oil, it had to be able to soak into the stone so it would stay permanently, but it couldn't make it slimy. My solution: mineral oil. I choose it because it soaks into things very well, and is widely avaliable. "But, Iv'e never seen it in a store..." yes you have, look at the ingredents in baby oil: 99% mineral oil, 1% fragrance (I know thats not the actual percentages, I'm going off memory). So I made another heart, and coveredit in baby oil, it's working great, I'll have to see the long term results before I put up a picture though...
If you want to put this on a necklace, follow my next Instructable: Stone Heart Pendant.