Real, Fake or in between?

Here is a question that most tribal skull collectors deal with every purchase. What is real and what is not? Let’s create a few categories:
1 – FAKE: A fake skull made of epoxy or plastic, plaster etc. Decorated like a tribal skull. Such a piece should cost no more than a couple of hundred euros.
2 – DECORATIVE: A real human skull, but not Dayak and not even Asian, decorated by an artist. This could be a “tourist piece” from outside Asia. This should not cost more than about 1200 euros
3 – GOOD DECORATIVE PIECE: The skull is Asian and the decorations are all Dayak. This could be a tourist piece from Indonesia, but not from Kalimantan. This should not cost more than about 1700 euros.
4 – DAYAK TRIBAL MADE PIECE: The skull is from Kalimantan and the decorations are not fanatasy. The engravings are a bit too clear, too deep. You can feel them with your hand without any troubles. The tribal skull is made by Dayak tribe members. This can be a tourist piece, but from Kalimantan. This should not cost more than about 2500 euros.
5 – REAL TRIBAL PIECE: This is what most collectors are always looking for. A real tribal piece. No signs of epoxy. Engravings are very gentle, you shouldn’t feel them too clear with your hand. The prices of these skulls start at about 2500 euro.
6 – REAL TRIBAL PIECE WITH GOOD PROVENANCE: Here’s the best deal. No explanation needed. The price can be more than 10,000 euros, but if you’re lucky you can find one for around 3,500 euros.