All-natural Oregon sunstone and similar-looking treated andesine once sold as natural are locked in apples-and-oranges competition that is both unfair and unnecessary....Until recently, brick- and salmon-red sunstone -- both clear and with schiller --were rarities. True, renewed mining of this feldspar in Oregon -- generally conceded to be the source of the world’s best sunstone -- brought more fine colors on the market than had been seen in years. But fine stones cost at least $100 per carat, usually far more.
Then, in early 2007, look-alikes costing $40 per carat suddenly hit the market in impressive numbers. None of its sellers called it sunstone. Instead, most called it andesine, which is a first cousin of labradorite (the scientific name for sunstone) in the plagioclase series of feldspars. [Plagioclase consists of six species, identified according to the ratio of calcium to sodium -- their two predominant chemical components.] This next-of-kin gemological status invited many consumers to think of andesine as an affordable alternative to pricier Oregon sunstone, especially because sellers swore it was all-natural. (2008) Complete Story