Yes, you are right that appraisal of jadeite, first you need to
identify whether it is A-jade (natural / little treatment), B-jade
(bleached and polymer impregnated), C-jade (dyed jade), B+C-jade
(bleached, dyed + polymer impregnated), D-jade (composite jade), etc,
i.e. jade imitation, e.g. serpentine, green grossular, averturine
quartz, green feldspar, etc. Then after you have done that, you need
to look at the quality of the jadeite-jade, i.e. texture, colour
saturation, translucency, quality of polish and symmetry. Then last
one, quite difficult, the price in relation to its quality and size
of the material.
Commercial quality is no problem but when you goes into high quality
where pricing can be quite difficult because in western countries
there are few people dealing with jadeite-jade as compare to diamond
or ruby or sapphire.
You cannot appraise a jadeite-jade through photograph because
picture can be altered or even upgraded to make it look perfect.
You can try visit a jewellery shop in downtown Chinatown in San
Franscisco to ask them to appraise your jade.