Opal Necklace comes in a great variety of types and styles. What we mean by 'types' is that there are at least three kinds of opal gemstone found in the outback of Australia in three basic areas. South Australia, NSW, and Queensland. But this is not a geography lesson. The focus is on that elusive and rare gem termed 'opal' which, according to historians has the meaning of 'a change of color' From what we can work out, the first type of opal found in this large continent was boulder opal and that was in the state of Queensland in the northeastern part of the country. So that this article doesn't ramble too much we will try to focus on this particular unique opal as it applies to necklaces, and leave a discussion of white opal, crystal opal, and black opal for another time. As the name suggests, Boulder Opal is often found in very large and also quite small boulder ironstones depending on the field. As the opal miner removes these stones from the ground, h...