The Blue Colour of Tekhelet

The Blue Colour of Tekhelet 150 150 Israel Ziderman

1. In my initial research, I considered that tekhelet was coloured violet (= purplish blue = bluish purple), because violet was the colour reportedly obtained from the colourless glandular fluid taken from the Mediterranean seashell trunculus חילזון . Furthermore, a violet colour corresponds to the chemical composition reported for trunculus-dye, consisting of a mixture of two dyestuffs, namely dibromoindigotin (DBI) and indigotin. DBI is a purple dyestuff, which is…

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Publication: ENIGMA OF THE SEPTUAGENARIAN MUREX 150 150 Israel Ziderman

Abstract ENIGMA OF THE SEPTUAGENARIAN MUREX Irving I. Ziderman   Abstract of lecture presented at the 28th Annual Meeting on Dyes in History and Archaeology, in  Poznan, Poland, on 22nd October 2009 Purple dyes from Mediterranean murex shellfish were among the most precious treasures of antiquity. There were two types. Tyrian purple (biblical argaman) was made…

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Tekhelet and the Banded Dye-Murex in Halakha

Tekhelet and the Banded Dye-Murex in Halakha 150 150 Israel Ziderman

The Sages determined two criteria in regard to the tekhelet: a “Tekhelet is kosher only when produced from a snail: that which is produced from any other source is disqualified” (Tosefta Menachot, 9, 6). b “And now we do not have tekhelet, but only white, because the source of the tekhelet has disappeared” ” (Midrash Bemidbar Raba,…

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Dyeing Process Was Fermentation

Dyeing Process Was Fermentation 150 150 Israel Ziderman

QUESTION Good afternoon Dr Ziderman, Recently, some people wanted to claim that the reduction processed used to dye with the murex dye is a recent discovery. Is it possible that the ancients were not aware of the reduction process and murex was in fact used as a mordant dye? Is there any way to verify…

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