It is amazing. Love the expression. Daniel Ipperti, historical painter I think, recognise the name. Most probably painted with oils.
I think the necklace is just black pearls that are coated with gloss. While this is truly great the lighting is harsh from above meaning that some of the effects are play with light on a GREAT sculpture (need to see it IRL to be sure). I have no doubt that you will see some great versions of this sculpt, I am not sure you can go wrong with it!