The ban includes popular—but expensive—brushes such as Winsor and Newton Series 7, Escoda Optimos, Richeson Siberian Kolinsky and Da Vinci Kolinsky, all known for their unique "springy" quality.
Kolinsky brushes are not made from sable martens, but rather from the tails of male Siberian weasels, found in Russia and northern China. Siberian weasels don't do well in captivity, so they are obtained by trapping wild animals.
Some have noted that the animals are trapped mainly for other economic uses, and that the tail fur can be regarded as a byproduct. In China, Kolinsky weasels are often regarded as pests because they kill chickens. But for those troubled by the ethics of brushes sourced from a wild animal, there are synthetic brushes that attempt to match the characteristics of Kolinskys, such as the Escoda Versatil Synthetic
The ban, which affects only U.S. customers, was brought about because the species was grouped into a list of endangered species, though the level of endangerment is reported to be relatively low. According to a Winsor and Newton spokesperson quoted on Artist's Daily, "Kolinsky Sable is not an endangered species."
Manufacturers of Kolinsky brushes are still making them, and U.S. dealers are still able to sell them as long as their supplies hold out, but it's illegal to import new stocks, even to do so personally.
Symi Jackson at Rosemary Brushes, mentioned that they are still manufacturing brushes made from materials that were purchased before the ban, and said, "At the time of purchasing all of the ‘Kolinsky Sable’ hair it was both legal and ethical. Indeed, it still is legal and ethical, though it is now under restriction in the US only."
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While stocks remain, it's still possible to purchase such brushes as
Winsor and Newton Series 7
Richeson Siberian Kolinsky brushes
Escoda Optimo Kolinsky
Da Vinci Maestro Series 35 Kolinsky Red
Winsor and Newton Series 7
Richeson Siberian Kolinsky brushes
Escoda Optimo Kolinsky
Da Vinci Maestro Series 35 Kolinsky Red
Further discussion and press releases at Arcane Paintworks