Allen

Sorry, I can not answer your question. I am far from a chemist and I do not
have the literature at hand. However there are some easily obtainable works
concerning this problem like for instance:

Baker, J.T., 1974. Tyrian purple: an ancient dye, a modern problem.
Endeavour, 33 (118): 11-17. (easily available in any university library).

The Israel Malacological Society published long ago an article dealing with
Purple dye literature up till 1982 by Spanier, Karmon & Linder: Levantina,
37: 437-447. Maybe I have still a few copies of it somewhere.

My friend Bram van der Bijl (the Netherlands) just paid my attention to a
little but very interesting booklet concerning Purple dye:

Edmonds, 2000. The mystery of Imperial Purple Dye. 41 p., 5 plts., 1 fig.
Softcover.

For those interested in the species which have been used for Purple dye over
the whole world, I refer to the old, but still valid work by:
Jackson, J.W., 1916. The geographical distribution of the shell purple
industry. Manchester Memoirs, 60 (7): 1-29.

Henk K. Mienis


----- Original Message -----
From: "Allen Aigen" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Monday, February 10, 2003 6:11 PM
Subject: Re: Tyrian purple


> Henk
> Did the urine degrade to ammonia in the hot sun, raising the pH and
changing the color?  Is a high pH necessary to 'set' the color so it won't
wash out?
> Allen Aigen
>
> ---------- mienis <[log in to unmask]> writes:
>
> Two reasons are given why the Phoenicians moved their Purple dye
production from place to place all around the Mediterranean basin:
> a. depletion of the local "Murex" populations;
> b. the enormous stench of the "mountains" of used "Murex" shells.
> In Lebanon "mountains" have been found of "Murex" shells with a length of
20 m, a width of 10 m and a height of 7-8 m. Inmagine the stench produced by
such an amount of foul-smelling snails in an area with a Mediterranean
climate.
> There is still another less known "secret" of purple-dyeing: the best
colours were obtained when the dye and the wool was mixed with human urine!
Sorry, but it's true.
>
> Henk K. Mienis
>
> [log in to unmask]
>
> ----- Original Message -----
>   From: Kay Peterson
>   To: [log in to unmask]
>   Sent: Saturday, February 08, 2003 3:26 AM
>   Subject: Re: Tyrian purple
>
>
>   Another shell, the Purpura, has also been used to dye cloth. My father,
who collected in Mexico during WW2, said that that dye stunk to high heaven.
(And he collected and cleaned many shells in his day without complaining
about odor.)  I noticed that no one in today's discussion has mentioned the
smell of these dyes.  Is it possible that Tyrian purple and related dyes do
not have an offensive odor?
>
>   Kay
>
>
> Allen Aigen
> [log in to unmask]
>
>