While the oldest rock ever discovered on the planet is an estimated 3.8 billion years old, you will find that today’s welcome stones can make either excellent housewarming gifts or gifts to yourself that will be just as timeless. The way that welcome stones are created is through a process called sandblasting which also happens to be used for making tombstones and cemetery markers. This is perhaps one of the reasons why welcome stones are also engraved to become a tombstone for a lost pet whose memory you wish to honor in your yard forever. Even thought the oldest engraved…