Monday, October 9, 2017

washing soda from baking soda

So, you having baking soda, NaHCO3, right? You can therefore make washing soda, also called soda ash and soda crystals, Na2CO3. It's very caustic so always wear gloves when you deal with chemicals, please!

Check out this blog to find out how

And this one to really hear about washing soda and soda ash.

Monday, May 29, 2017

Exploring "Italian pink" and "Dutch pink"

"Dutch pink"and "Italian pink", probably actually green and yellow pigments, are mentioned to in a note in De Arte Illuminandi (Thompson and Hamilton 43).

68 For the identification of these prugnameroli as buckthorn berries (buckthorn = It. spincervino, spino gerbino), fruits of varieties of the buckthorn, Rhamnus, see Cennino, ed.cit., II, 32, n. 1. Two pigments were and are derived from Rhamnus berries: a yellow and a green. The product of the unripe berries is the Giallo santo (cf. M. P. Merrifield, op.cit., I, clxiv), known in English by the extraordinary names, "Italian Pink" and "Dutch Pink." The juice of the ripe berries yields the pigmentum e fructibus rhamni catharticae, succus veridis, listed by H. L. Gerth van Wijk, Dictionary of Plantnames, I, 1135, among the technical products of R. catharticus, the color known in English as "Sap green," the Italian verde di vescica (so called because the inspissaded juice was preserved in bladders), the Safftgrien of Valentin Boltz, who specifies, ed. cit., p. 75, that it is to be made from "krutzber, die man auch nent hagenberlin," gathered "ungeforlich vierzehn tag vor Michaelis" (that is, about September 15). For the yellow color, ibid., p. 72, "Du must gar eigentlichen warnemmen der zyt diser hagenberlin im Augustmonat, daz sy nit zu satt oder zu alt werden." If, therefore, in Alsace, the color came out yellow if the berries were gathered in August, and green if they were gathered about the middle of September, we may probably assume that the quality of green yielded by these Rhamnus fruits was not entirely definite. It must have varied in it's content of yellow, according to the date and nature of the season. (Thompson and Hamilton 43)
As well as the Introduction of Medieval and Renaissance Treatises on the Arts of Painting: Original Texts with English Translations by Mrs. Mary P. Merrifield.
Giallo santo was a kind of yellow lake, which was made from various plants. It was sometimes prepared from the berries of the buckthorn (note leads to p 708, her translation of the Paduan Manuscript recipe) (spincervino)...
The French call pigments of this description "stil de grain," and include under them not only these pigments which are a pure yellow colour, but such as incline to green. The English term for this class of pigments is or was "pink" Thus we have "Dutch pink," "Italian pink," "brown pink," &etc. (Merrifield I, clxiv)

So, for tonight, that is my search and citation of sources. Pigment Compendium also references Italian, Dutch and brown pink but that transcription is for another day.

Monday, February 27, 2017

Word of the Week: pigmentary


[pig-muh n-ter-ee]
1. of, pertaining to, having, or producing pigment.
Origin--1425-75; late Middle English: a dyer < Latin pigmentārius.  

Monday, January 16, 2017

2016 Buckthorn with vinegar paint results

Here are the paint results from these buckthorn and vinegar recipes in 2016.

I was able to make a nice sap green from the buckthorn with white wine vinegar by adding a little potassium aluminum sulfate (alum).

Note that the 25% acidic vinegar and buckthorn produced a thick juice that required more thinning and would require more water and more gum Arabic to produce a smooth paint.

When I added alum to both buckthorn and vinegar recipe it resulted in green!  By itself, the results were less satisfying and not what I would call green but more blue gray.

Side note: I think the shininess on the first two swatches is the result of a little too much gum Arabic.

Buckthorn with vinegar, twice in 2016

In 2016 I tried twice more to get green for paint or dye/stain from buckthorn.

Bolognese MS De Tintis ad Tigendum Pellum (Merrifield 426)

Sunday, January 15, 2017

2016 sap green from Buckthorn Experiment 2 Results

This experiment began in November 2016 and was finished up at the beginning of 2017.

The ripe buckthorn, Rhamnus spp., juice had been extracted from refrigerated, and slightly dessicated buckthorn berries from Saco, Maine. The berries were reconstituted with distilled water (DW), and then rock alum (potassium aluminum sulfate) was added to the juice.  Commercially available gum Arabic was then used with distilled water to paint it out on 12/23/16.

By 12/29/16 the dark blue had turned to dark green and further trials were performed. 

The change of color from blue to green suggests a few possibilities to me.  Either the alum had a chance to change the buckthorn after sitting with it for a while or it could have come into contact with calcium carbonate contaminates from the enviornment like egg or clam shell (neither of which are scarce in my house) or the Strathmore Bristol vellum finish paper is prepared with a buffer that reacted with the acids and berry juice. 

Further trials were painted out from the original berry juice with alum in the palette and shell with gum.  More distilled water was used to re-hydrate the paint and thin it out for greater visibility.

The juice with alum alone, in a clam shell and with crushed egg shell all yield what I would describe as a gentle sap green.  The trial with lye turned from a rather interesting olive to quite a bright yellow reminiscent of the yellow yielded from the green buckthorn drupes and in another ripe drupe recipe discussed here.

Buckthorn sap green Experiment 2, 2016

Merrifield 420 with variables