Symplocos is a bio-accumulator of aluminium, like club moss. This gives us the opportunity to make a 100% plant-based, lasting color. The powdered bark of the symplocos tree replaces aluminium sulfate in traditional dye recipes. Use before natural dyes or eco-printing for improved light-fastness and wash-fastness. Some colors like logwood and madder will look different than when using regular alum.

It is hard to give an exact recipe for using symplocos, as there are many variables here that make a difference.
For WOF use 20-100% WOF, this sounds ridiculously vague, but it depends on fiber type and time. As a rule of thumb, start with 50% WOF and play around with the amounts as you gain experience.
Silk needs less than cotton, thicker weaves will need more than thin weaves. The longer you heat symplocos in water, the stronger it will be.

Use soft water. If your water is very hard, use Calgon or add 0.5g of cream of tartar per liter of water.

Heat the symplocos in water and boil it for at least 30 minutes. The symplocos will sink to the bottom of the pot. If you are dyeing yarns: filter the mordant water to avoid the 'grit' getting stuck in your yarn.

For silk: Heat the pre-wetted silk in the symplocos mordant liquid for 90 minutes at 70ºC. Heating more can damage the silk. Rinse in tepid water, your fabric should be a pale shade of yellow. The yellow will disappear after dyeing.
For cotton: Boil the symplocos liquid together with the cotton for 30 minutes. Rinse in tepid water, your fabric should be a pale shade of yellow. The yellow will disappear after dyeing.

You can re-use a symplocos mordanting bath once with lighter results.