Blackish blue copper pipes?

[Todd]

Hi All,

I live in Northern Nevada.

Had to take a trip under the house. I noticed
that all my fresh water copper pipes are covered,
elbows and all, with some very dark blue compound,
as if they were painted. A bit of sandpaper reveals
copper.

Any one have any idea what this dark blue stuff is
and what it is used for?

Many thanks,
-T

 

[Sjouke Burry]

Hi All,

I live in Northern Nevada.

Had to take a trip under the house. I noticed
that all my fresh water copper pipes are covered,
elbows and all, with some very dark blue compound,
as if they were painted. A bit of sandpaper reveals
copper.

Any one have any idea what this dark blue stuff is
and what it is used for?

Many thanks,
-T

Copper oxide. Or rust.

 

[Todd]

Copper oxide. Or rust.

Copper oxide is light blue (cyan) and is cakey. Not iron pipes,
so no rust. It has definitely been painted on -- have stroke marks.

Of interest, the plumber that went down to repair the
leak in the pipe comes from three generations of plumbers
and they could not figure it out either.

-T

 

[Frank]

Copper oxide. Or rust.

Oxides, sulfide, carbonate, sulfate - all colored.

 

[Todd]

blue on copper could be copper sulfate.
copper oxide is dark brown/black.

The plumber did say it smelled slightly of sulfur
under the house

 

[Molly Brown]

Hi All,

I live in Northern Nevada.

Had to take a trip under the house.  I noticed
that all my fresh water copper pipes are covered,
elbows and all, with some very dark blue compound,
as if they were painted.  A bit of sandpaper reveals
copper.

Any one have any idea what this dark blue stuff is
and what it is used for?

Many thanks,
-T

This is just a wild guess: Is it possible that it may have been
applied by an exterminator. Many bugs drink the condensation that
forms on pipes.

 

[Todd]

From my chemistry days, copper sulphate is
intensely blue. Can't remember about sulphide.

Christopher A. Young
Learn more about Jesus
www.lds.org
.


The plumber did say it smelled slightly of sulfur
under the house

intensely blue to the point of being black

 

[Todd]

This is just a wild guess: Is it possible that it may have been
applied by an exterminator. Many bugs drink the condensation that
forms on pipes.

Ah ha! I bet you are right! The plumber comes back tomorrow.
I will mention it to him.

Thank you!

-T

 

[Todd]

Todd wrote the following on 6/12/2012 8:42 PM (ET):

Perhaps it was painted in an attempt to prevent the greenish colored
oxidation that copper is wont to produce.

But who sees it in the crawl space?

 

[fred.flintstone]

Perhaps it was painted in an attempt to prevent the greenish colored
oxidation that copper is wont to produce.

--

My uncle used to paint all the galvanized pipes in his basement with
aluminum paint (silver paint). Since galv pipes are already silver
colored, I never understood that..... But he did like to putter around
in the basement, that was his favorite place, so I can only guess it was
his form of decorating back in the 1960s.

 

[bob haller]

My uncle used to paint all the galvanized pipes in his basement with
aluminum paint (silver paint).  Since galv pipes are already silver
colored, I never understood that.....  But he did like to putter around
in the basement, that was his favorite place, so I can only guess it was
his form of decorating back in the 1960s.

when i was a child some of our copper pipes were discolored like that,
a very dark blue black. realtives said it was corrosion. the pipes
were near the laundry which according to grandma was where the copper
boiler was...... originally they boiled clothes to clean them.

so that area was super moist/