Re: Copper

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

Posted by Catherine Cartwright Jones on May 3, 2001 at 16:45:59:

In reply to: Copper posted by mark on May 3, 2001 at 15:58:26:

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.

Follow Ups

Re: Copper mark 17:15:14 5/3/2001 (1)
- 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.
Optional link URL:
Link title:
Optional image URL: