[Avodah] ID of chilazon vs. chagavim

[Micha Berger]

On Fri, Aug 08, 2008 at 05:10:59PM -0400, Yitzhak Grossman wrote:
: Actually, the Radziner [0] seriously considers the possibility that dye
: derived from *any* animal species [1] is acceptable for Techeles, as
: long as it satisfies the crucial colorfastness criterion.
: 
: [0] Ma'amar S'funei T'munei Hol, end of 'Ha'ta'anah ha'shniah', pp.
: 18-19 in the YM 5743 edition

I didn't think this was his masqanah.

The Tif'eres Yisrael seems to say this in general -- that chilazon was
simply the only known source of a colorfast blue dye in antiquity.

R' Tzevi Hirsch Kalisher is medayeiq in the Rambam Tzitzis 2:1-2 and
concludes that the need for specifically a chilazon is a din in tzitzis.
For bigdei kehunah, he holds only the color and colorfastness are
me'aqvim. See Liqutei Halachos Zevachim ch 13 67a. As you would guess,
the majority disagree.

: [1] He says 'kol minei halazonos u'tolaim', but in context it's clear
: that he means any animal species

Yes, something to do with animal sticking to animal with a fastness that
vegetable dye wouldn't. Sounded like pre-modern chemistry, actually.

Both would have to conclude that qaleh ilan is not as colorfast. The
Baal Techeiles says so explicitly, and the TY must or else qaleh ilan
would not be a problem dye leshitaso. (RZHK has no such problem, as
the warning about qaleh ilan is made in the gemara WRT tzitzis.)

Tir'u baTov!
-Micha

-- 
Micha Berger             It isn't what you have, or who you are, or where
micha at aishdas.org        you are,  or what you are doing,  that makes you
http://www.aishdas.org   happy or unhappy. It's what you think about.
Fax: (270) 514-1507                        - Dale Carnegie