As Tahitian Black Pearl has different reflection properties than my pearl in video. And it is also Back with slight touch of Dark Green. So you have to understand it from reference and create it with method shown in video above. and I would play with this colors: #11353D, #000F09, #0A271C, #215748, #2A4E42. HeadStart for you: Start with Base color #000F09. I'd Love to see it you make. Good Luck.
Take these 3 images as reference: 1) www.lovelypearl.com/UploadPic/Necklaces/big/p18_South%20Sea_Black_Pearl_Necklaces_2.jpg 2) www.multicolour.com/pearl/tahitian-cultured-pearls.jpg 3) EASY ONE: sep.yimg.com/ay/americanpearl/8mm-black-south-sea-tahitian-pearl-earring-3.jpg
