My moissy has not stained at at, but I actually give it a frequent bugg with a Sunshine Cloth (platinum setting) to keep ahead of the potential. It does not seem inevitable, as PP mentioned. Many many moissy owners have no staining and some do. Why? I understand the chemistry at hand, but not why there is so much variation. I think eventually, they will either coat them to prevent the passivation or get the base-material to actually have a depositted layer that is clear, as it done in industrial application. Keeping in mind that many commonly work gemstones come with some problems, morganite and other beryls attract oils which reduce brilliance, emeralds are incredibly fragle, sapphires/rubies are subject to becoming scratched.
Which material works for you is hard to say for us. If you have a $2k budget but want a high color over 1 carat, that won’t happen with a diamond (lab or mined), pre-owned or antique. If you have a $6k budget with the same wants, you can get your wants in both a lab or mined option. Back when my grandmother was a jeweler, it was quite common for someone to get a smaller diamond they could afford with excellent cut/light return and the upgrade that to a side-stone of a 3-stone setting or earring upon a major anniversary when funds are more available. In those days, trade-up policies were really not around, now Whiteflash and HighPerformanceDiamonds offer 100% of the value of your diamond toward an upgrade with them, provided the upgrade is $1 more.
The environmental argument is complex and as PP said, the metal and solders used for settings come with their own harm. But, neither moissy or lab diamonds contribute to blood-wars, expect by the face that the maintain demand and that demand maintains the conflicts. With any environmental argument, there is no single answer, rather it is a weighing of which elements of the argument are more important and look at the ‘full environmetnal’ cost. Many “green” technologies fail when put into full-cost-accounting of harms, yet people still find the carbon offset compelling. Neither is right or wrong, it is how you weight the portions of the benefit and harm.
For moissanite, the question is usually what performs most like a diamond. Here’s my list for rounds… I think the old cuts are better than modern. That said, here is how I rank the modern rounds (in order, I always prefer near colorless/GH over the higher colors for realism): NEO diamond cut, Harro Round, SuperNova (not a H&A style cut), Amora Eternity, F1 Hearts & Arrows. For shape, rounds are more dimaond like than fancies, but I’ve been impressed with some of the cushion. The ovals look ‘too perfect’ but with the new super-ideal oval diamond being released soon, that may be less of a “tell”. Fire and Brilliance on Youtube have fantastic comparison videos (https://www.youtube.com/watch?v=Qu3MCh78Gz4).
For lab diamonds, D.Nea will sell to the public and PureGrown and Chatham sell through vendors. But, selecting a lab diamonds is exactly like selecting a natural diamond except that neither of the top grading labs will grade lab stones (GIA and AGS), so you need to be more careful with the rating outcome.
These are measurements to help you stay in ideal cut territory and apply for mined and lab.
crown angle: 34-35.0 (up to 35.5 crown angle can sometimes work with a 40.6 pav angle)
pavilion angle: 40.5-40.9 (sometimes 41.0 if the crown angle is close to 34)
Once you find a diamond that meet these, you can use the HCA Tool to find complimentary angles. If the stone score under 2.0, request and ASET or Idealscope to see how it perforns.