The reason that discoloring/clouding/scratching is not a major issue with Asha is due to their use of amorphous diamond-like carbon coating that is infused into the upper layers of the substrate (the stone). This coating, which is similar to the coating used on Chopard's Mille Miglia Speed Black but higher on the DLC scale and unique to Asha, is what allows the stone to not only be scratch-resistent (in part to its now FAR lower friction coefficient) but also impermeable to water, air, dirt and dust, the very common things we come into contact with everyday that inevitably ends up clouding an ordinary cubic zirconia. There are few, if any, other companies seriously doing this with their stones because of the research involved and "extraneous" costs; most companies simply do not want to invest in improving diamond simulants because there is typically fatter margins in real stones and most companies who sell diamond simulants of any kind also sell mined diamonds; they would not want to risk killing this cash cow for anything. So many buyers simply do not care about socio-environmental impact of the mined gem industry, which still makes up the lion's share of the jewelry sector.

Although BTD does sell natural diamonds, it is not the bulk of their business like many other firms. They sell them because clients rave about their total experince with BTD to everyone (anyone!) and not all these new individuals have seen the simulant light causing these clients to lean toward mined stones. BTD would hate to send their business across the street and are just being comprehensive, for which I cannot really blame them. This mirrors the situation I mentioned above with firms who sell primarily mined diamonds but also simulants. However, the core of Betterthandiamond.com's business is in simulant, synthetic and cultured stones/pearls. I simply cannot say enough good things about Wink and his team. Buy (V5!) in total and complete confidence.