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Using UV to help identify gemstones

Does anyone have any experience using UV light to help determine what a gemstone is and whether it is synthetic or not in conjunction with the RI of the stone? The color is as follows:

GWLAb: Vivid Purple

GIA: Medium dark, Moderately Strong, Purple

This particular stone is supposed to be a purple sapphire.

The following is what it looks like under short wave UV light from my UV light cabinet.

The following is what it looks like under long-wave UV light in the light cabinet.

The RI is 1.768

Is this synthetic?

After posting this, i found the following article:

I therefore think the stone is a natural heat treated sapphire. Please let me know your thoughts.

also found this article

I found straight growth lines. Using UV is also much faster when going through many gems. I normally receive about 800 stones from suppliers at any one time and I have to quickly sort through them. Then i go through the gemstones I am interested in in more detail. Then i usually have five days to fully inspect the gemstones before i have to either pay for them, accept them on consignment, or return them. Using UV is a very fast method of quickly sorting through the stones.

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I forgot that I have an extensive library of synthetic corundum… so here is a photo of one of the stones i’m trying to identify next to a small synthetic sapphire.

it reacts to short wave UV and is totally inert to long wave UV. Below is the photo of SWUV.