Re: Copper

[ Follow Ups ] [ Post Followup ] [ The Henna Page Forum ] [ FAQ ]

Posted by mark on May 3, 2001 at 17:15:14:

In reply to: Re: Copper posted by Catherine Cartwright Jones on May 3, 2001 at 16:45:59:

: Copper oxides are used in some khidab and some harquuses ....
but....
: the toxicity bothers me. Copper is a tad poisonous. I tried mixing
: henna with copper oxide ... no dif that I could see. I tried
throwing
: pennies into a batch. No real dif that I could see.
:
: Anyway .. it makes the henna go drabber, if anything, (and I've not
: seen much evidence of that) not redder.
:
: It doesn't make it last longer.
:
: Most of the metal oxides do not penetrate the skin at all
: (fortunate!).
: Once I added black iron oxide to the mix, and for a brief moment, I
: thought the henna was MUCH darker ...BUT ... I rinsed my hands and
: away went the black! It was just sitting there. Never penetrated
at
: all.
:
: I think it is possible that perspiration interacts with metal and
: creates a condition that favors much darker henna ...but that's
: chemically a bit beyond my ken. Some of the metal mixing bowls
from
: India are silver-colored but have a high copper content. I don't
: think copper is actually getting into the henna, but the acidity of
: the paste is reacting with the copper to change something. Copper
is
: very reactive with oxygen, and that might be changing that loose H,
or
: the double bound O on the hennotannic acid molecule. Henna paste
: appears blacker when it touches copper, but I haven't seen it stain
: blacker. Many natural dyes change color dramatically when you
simmer
: the acidic dyebath in copper vs enamel pots. The copper oxide does
: seem to percipitate some vegetal acidic dyes into another
: color,(usually drab and dark) but beyond telling you that, I can't
: help. Oak gall dyes (gallotannins, related to hennotannins) will
: stain darker if a handful of copper salts are thrown into the
dye ...
: but its a poisonous thing to do.
:
: Many of the pre-made pastes have some heavy metal oxides, that seem
to
: be be behaving similarly to what I just described. They make henna
: darker.... maybe... but the color is that drabbish color, not the
: vibrant natural henna color. And ...
:
: Do you really want to put something into henna that is an
: environmental yucko? Copper oxides can be nasty when not in their
: proper place.

It was a debate at the studio yesterday .....why i was asking.

I would personally not like to add it to henna ......the debate was
why use silver or copper bowls for mixing!

Follow Ups

Re: Copper Catherine Cartwright Jones 19:34:14 5/3/2001 (0)

Post Followup

Name:
E-Mail:
Subject:
: : Copper oxides are used in some khidab and some harquuses .... : but.... : : the toxicity bothers me. Copper is a tad poisonous. I tried mixing : : henna with copper oxide ... no dif that I could see. I tried : throwing : : pennies into a batch. No real dif that I could see. : : : : Anyway .. it makes the henna go drabber, if anything, (and I've not : : seen much evidence of that) not redder. : : : : It doesn't make it last longer. : : : : Most of the metal oxides do not penetrate the skin at all : : (fortunate!). : : Once I added black iron oxide to the mix, and for a brief moment, I : : thought the henna was MUCH darker ...BUT ... I rinsed my hands and : : away went the black! It was just sitting there. Never penetrated : at : : all. : : : : I think it is possible that perspiration interacts with metal and : : creates a condition that favors much darker henna ...but that's : : chemically a bit beyond my ken. Some of the metal mixing bowls : from : : India are silver-colored but have a high copper content. I don't : : think copper is actually getting into the henna, but the acidity of : : the paste is reacting with the copper to change something. Copper : is : : very reactive with oxygen, and that might be changing that loose H, : or : : the double bound O on the hennotannic acid molecule. Henna paste : : appears blacker when it touches copper, but I haven't seen it stain : : blacker. Many natural dyes change color dramatically when you : simmer : : the acidic dyebath in copper vs enamel pots. The copper oxide does : : seem to percipitate some vegetal acidic dyes into another : : color,(usually drab and dark) but beyond telling you that, I can't : : help. Oak gall dyes (gallotannins, related to hennotannins) will : : stain darker if a handful of copper salts are thrown into the : dye ... : : but its a poisonous thing to do. : : : : Many of the pre-made pastes have some heavy metal oxides, that seem : to : : be be behaving similarly to what I just described. They make henna : : darker.... maybe... but the color is that drabbish color, not the : : vibrant natural henna color. And ... : : : : Do you really want to put something into henna that is an : : environmental yucko? Copper oxides can be nasty when not in their : : proper place. : : It was a debate at the studio yesterday .....why i was asking. : : I would personally not like to add it to henna ......the debate was : why use silver or copper bowls for mixing!
Optional link URL:
Link title:
Optional image URL: