Sap Green 1 from Buckthorn berries, medieval paint recipes,

There are many medieval sources with recipes for Sap Green, the beautiful paint and pigment used to provide green in medieval miniatures and to dye skins green among other things.

My first Experiment to produce green with Buckthorn was one from Mary Merrifield's Original Treatises, a 15th century recipe from Bolognese MS De Fiendis Veridibus (Merrifield 426)

I picked the berries in August in Westbrook, Maine.  Here's that first recipe:

Mary Merrifield's Original Treatises pg. 426

As the recipe suggests the day after picking the berries I combined about fifty grams each of ripe berries and Hannaford white vinegar of 5% acidity in a glazed sauce pan and heated it at gas mark two on the simmer burner of my stove.  At two minutes I noted that it was steaming, at four forming bubbles.  Five minutes in it was spattering so I turned it down to low and simmered until the weight of the mixture had reduced by about half which took about thirty-five minutes.  I poured it all into a square of washed clean linen secured over a canning funnel over a glass jar then squeezed as much liquid as I could into the jar.  The liquid looked dark purple.  Several days later I painted it out.

The alum water I used in the following paints is pure alum, Aluminum Sulfate, Al2(SO4)3, and distilled water in a 1:10 ratio.  This should make an acidic solution.

"A" consisted of a drop of the buckthorn and white vinegar juice as well as Winsor Newton Gum Arabic.  It painted out blue then turned green the next day.
"B" a drop of the vinegar-buckthorn berry juice, one drop of the gum water and a drop of alum water.  It painted out green immediately.

A on the left, B on the right.  Still wet B is already green.

"C" is the same as A in a clam shell, it painted out red purple-y and turned green by the next day.

"D" is C, juice and gum in a clam shell, with a drop of the same 1:10 alum water in B and like B it painted out green and stayed green.

Ultimately there will be an updated picture of after all of them turned green and one of my notes too!

And more experiments:
Experiment 2