It's highly adulterated, just like many other supplements, but more so because of the price.

It's actually pretty cheap as a supplement. Needs to be a standardized extract from a reputable manufacturer.

Standardization will typically include either:

1. Crocin, Picrocrocin and Crocetin

2. Safranal

Or a combination of all of these.

Dose 20-50mg depending on the extract.

If you opt for saffron threads, then again, make sure you get them from a good source.