The New York Times published an insightful article on the increased production and sale of extinct mammoth ivory, August 7, 2017.
Weaning Itself From Elephant Ivory, China Turns to Mammoths
The article notes the source of this new, legally saleable ivory is the melting permafrost of Russia’s Arctic. But it also quotes an expert, Mark Jones, associate director for policy for the Born Free Foundation, a wildlife conservation organization based in London, who said "As long as there is a legal trade in mammoth, ivory of all kinds can be laundered into it."
Carving mammoth ivory tusks at a workshop of Jin Sha Mammoth on the outskirts of Beijing