Friday, 23 February 2007

A good wash

first posted 2/24/06

Good washing of the lakes is important lest residues of alum or the lye remain, this shows up as a bloom when drying in the dish, you knwo when the lake is clean when no bloom rises when left standing for a few days.

I attempted to liberate the brazil red colour in oil, some plants liberate colour in oil, brazil did not, at least not in cold oil, I suspect it wont in hot either. The idea was based around the principle of creating an oil glaze straight off rather than making a lake then drying it then grinding it with oil. I guess the insolubility of the brazil is why I can find not one mention of such a process but dozens about using lye and alum etc for creating the lake in the first instance.

Also I found out that hard water has an adverse effect on brazil, I normally used boiled water but lately forgot and it meant that much of the calcium (carbonates/sulphates?) in the water reacted with the alum and pigment creating a useless sediment on the bottom of the test jar. It also seemed to reduce the yield. I realise that the red is increased by adding alum but this was a noticable drop in yield, so all water must be low in mineral content. I understand that dyers have to take into account the hardness of water in their regions.

Madder lakes coming soon, had a quick go the other week, results were that the colour is a brownish red going to garnet depending on pH, made a nice peachy pink chalk precipitate with it though, but am looking for the reds mainly.

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