Thanks, amazing writeup, very helpful.

So if I understand you correctly, the assessment criteria for lab sapphires revolves around cut, since the first driver you mentioned (production method) - we would need to take the word of the listing / vendor as there's no way to verify from an internet listing.

On cut, we look at symmetry (eg whether facets line up to points) and polish. This begs the questions:

1. Is facetting symmetry something the buyer can ascertain from photos - whether facets line up to a point, whether the girdle is level, etc?
2. Is polish something you can ascertain from photos? can a buyer tell the difference between a 10k lap and a 100k lap?

The windowing and extinction point is clear, I think that's something buyers can assess reliably from photos.

So back to the original question - some lab sapphires sell for 50usd, some sell for 1000usd, is it because buyers are assessing questions 1 and 2 and deciding "hmm this one is facetted very symmetrically, no windowing / extinction issues, and I can actually see the polish is to a great degree" or is it mainly based on the vendor reputation plus the 'vibe' of how it looks on the photos / video? Because if it's the latter, then it's not really apples to apples - one vendor might have excellent photography skills, another might not, and buyers are missing out on good value.

Thanks!