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Uses for "Blue Stone" copper sulfate

A discussion started in 2003 & continuing through 2017 -- add your Q to bring it back to the Hot Topics page.


Q. My 95 year old mother recently passed away. In going through her house, I came across a small round container of "Blue Stone" copper sulfate [linked by editor to product info at Amazon]. On the front, it said POISON, not for medicinal use. On the back, it said ..."of highest quality and packed under the personal supervision of a registered pharmacist or chemist. For what purpose is "Blue Stone" used?

June B. Ewing
- Americus, Georgia

Folk Remedies That Work

Oddball Ointments, Powerful Potions, ...

The Old Herb Doctor


A. I'm 47 years old, at the age of 16 I started to get an occasional ulcer in my mouth. I went to my small town doctor. Living in the west Texas town of Hamlin he prescribed blue stone. My father knew this to be an item used to kill moss in stock tanks that had been banned. I was sent down to the local drug to get the blue stone. Where three or four rocks were put in a white match box. There was no charge for them. When a ulcer would develop I would take one of the rocks out and place it on the ulcer , mouth or ulcer being wet and hold it on there as long as I could stand it. This would cause a little discomfort but not any worse than the pain of the ulcer itself. This would generate a lot of drool or slobber. The taste was very bitter.I was told not to swallow the spit or rock. one or two applications and no more pain. I rinsed the rock off, put it back in box until the next time.

Over the years I have used up my supply and would go back to the same drug store and get a few more rocks. I only get these ulcers a few times a year. I am out of blue stones at this time. Several years back I ran out and tried to find it locally (Fort Worth) at Eckerd drug . They had no idea what I was talking about and called the ulcer a canker sore and I bought a ointment for that . This was really ineffective or took so long to get rid of. The Eckerd pharmacist told me of another drugstore to whom I spoke with on the phone that thought they had what I was talking about but was in a very small rock form I never got any to try. Now having the internet and the ulcer I am trying to find blue stone in the same size I used to have without having to make a three hour drive to the old small town drug store.

Mike Norris
- Granbury, Texas


Hey Mike, I just found a gallon of that stuff at my grampa's.

Steve Harrell
- Zolfo Springs, Florida


A. Copper sulfate is used for algae killing and as a pesticide/herbicide.

Louis Rendemonti
- West Chester, Pennsylvania


A. Copper sulfate crystals can be dissolved in water in a "foot bath" for sheep to pass through regularly as a prevention/ cure for "foot rot".

Morris Conklin
- Loures, Portugal

April 16, 2008



A. Hi, Kiki.

From running this site for 20 years, I can tell you that people never reply to postings like yours because they can't even start without committing a half-hour to an almost endless string of "If ..., but if ...., and if ..., but if ..."
Please take your time and very carefully explain your actual situation and the context behind your question, and you'll usually get a helpful response. Thanks.

Good luck and Regards,

Ted Mooney,
Teds signature
Ted Mooney, P.E. RET
Pine Beach, New Jersey

August 16, 2008

Q. I was just browsing the net looking for Blue Stone (copper sulphate)
I have an old family recipe for icicle pickles that uses the blue stone as a coloring agent - the recipe calls for " enough blue stone to cover a Dime" and this is mixed into a gallon of water for processing -
I have been unable to find any anywhere -

Carl Ethier
- Red Deer, Alberta, Canada

September 22, 2008

A. in the late 40's early 50's my grandmother sent me to the pharmacy to purchase bluestone. It was in powder form and my grandmother used it to enhance the green colour of 9-day crock pickles. The recipe called for "the tip of a knife" of the bluestone. I ate a lot of those pickles.

grace bellamy
- Vancouver BC Canada

Copper Sulphate 10 pounds

February 26, 2009

A. You can get bluestone at gardening stores very cheaply, as copper sulphate =>

Brad Heyd
- Duncan, BC, Canada

April 21, 2010

A. My family uses bluestone for pickles. We have an old bottle we still use. Makes pickles a wonderful green color. We have used it for four generations now that I know of with no side effects.

D Haueter
- Grand Ledge, Michigan, US

July 14, 2009

Q. My grandmother, now passed, always kept "Blue Stone" on hand to cure warts. She would soak the rock in water, then using a toothpick apply it to a wart. She always said it was a Modoc Indian remedy. Has anyone else heard of this? I just purchased some Copper Sulphate at the feed store. Does anyone think there might be side effects to this remedy?

Rena Haley
- Sacramento, California

Wart Remover

July 14, 2009

A. Hi, Rena. Although it doesn't seem to me that it would be particularly dangerous, our sensibilities are a little different these days. I wouldn't do it, but would use a commercial preparation =>
(they have salicylic acid in them) because I personally know that they work very well. Good luck.


Ted Mooney,
Teds signature
Ted Mooney, P.E. RET
Pine Beach, New Jersey

sidebar August 6, 2009

If anyone is interested I use copper sulfate in my swimming pool for approximately 10 years now as a start up/shut down and maintenance product for all types of algae. In 10 years I have never had a problem with a green pool. My neighbors and family always comment on how beautiful the pool is with it's shimmer and clarity. I have recommended it to many others who now enjoy an algae free pool. I love this stuff and easily find it in farm supply stores.

Marlo Murphy
- Elktom, Michigan

August 26, 2009

In relation to the use of copper sulfate in swimming pools what ratio of the chemical to gallons of water do you use?

- Winnsboro, Louisiana

July 3, 2012 -- this entry appended to this thread by editor in lieu of spawning a duplicative thread

Q. Could the Blue stone be used in a pool? To clear the water.

Mariane Sawatzky
- St. Anne, MB, Canada

July 5, 2012

A. Hi Mariane.

I've seen it done, but don't think it's a great idea. I don't think copper belongs in a swimming pool. It is used to control algae in ponds and lakes though.


Ted Mooney,
Teds signature
Ted Mooney, P.E. RET
Pine Beach, New Jersey

August 16, 2012

A. I had to take care of my retired neighbor's in-ground swimming pool this summer for 40 days (as well as my own). His pump fuse worked for 10 days after he left, then no more water circulation for 15 days. During this 2 weeks I did not put in any chlorine. During this time, his water stayed VERY clear whereas in my pool I was at war with algae. To add detail, last year I changed the vinyl liner (so all of the water too) and this spring the sand in the filter of my in-ground swimming pool.
So when he came back I asked him to give me his recipe. He give me the blue stone powder. Incredible what a half of a tea spoon can do. The background in the pool turns from green to the color of the liner.
He let me read a paper guideline and it says:
- put half of a teaspoon every 10-15 days.
- no risk for health as you can swim right away.
- put the blue stone in the skimmer
- let the pump work for at least 12 hours.
This is my first use today.
Hope it helps. My neighbor is in good shape as well as his wife and relative who use his pool. 10 years I know him.

Alexandra Legrand
- Montreal, QC, Canada

October 14, 2012

A. I am 84 years old and I have been taking care of my 13,500 gal in-ground pool since my Hubby's demise. I have battled "green pool" problems several times. A friend told me about using BLUE STONE in his lake for an algae problem. I woke up one morning this summer with a GREEN POOL. To battle this condition before, I had used 5 jugs of Chlorine and a pkg of shock. Running the filter 24 hrs per day and cleaning the filter EVERY MORNING. I went on line and read that it had been used with success for a like problem. Having NOTHING TO LOSE, I got some POWDERED BLUE STONE from my neighbor. I placed one tablespoon of the blue stone powder in a 2 gallon plastic watering can. I went around the pool edge sprinkling the concoction in the water, until it was all gone. I set the filter pump to run 24 hrs per day. In 8 days of cleaning the filter EVERY MORNING, the pool water went from green to a murky gray to clear.

Shirley Carter
- Sarasota, Florida

January 7, 2011

NO, do not introduce into any streams or rivers ,
Use only at recommended concentrations in ponds for algae control or fish kill will occur.
Since copper bauxite and other ores/minerals are naturally occurring and this soft metal stays around for a long time I know that few plants will grow in soil heavily treated with this stuff. Sulfates are hazardous also for fish.

Bart Storey
other agency - kansas city, Missouri, usa

June 2, 2014

A. I use Copper Sulphate in my pond to clear up the Algae.

- WINDSOR, Virginia USA

October 29, 2009

Fascinated to read this

I am a doctor and used to work on a Scottish island in 1991. Occasionally there would be a wound that over-granulated - this means that there was some 'proud flesh' that developed, usually dusky purple red and bled easily. My boss would tell one of the nurses to use the 'blue stone' which was a large crystal of copper sulphate in a jar.

The crystal was rubbed over the tissue on the wound and the tissue would change to a brownish colour. The crystal was then washed and left to dry for the next time. being very soluble, a small quantity of the copper sulphate would have dissolved onto the tissue. Within a few treatments the over-granulation would shrink and the wound healed very well.

Naturally, this goes against most modern infection control procedures and 'single use' policy and I do not know of any work to study the ultimate safety of it being used in this way, but I wanted to share with you my experience of the blue stone in fairly modern times.

Ewen Sim
- Liverpool, UK

January 28, 2013

Hi Dr. Sim. I read about that treatment in "Cutting for Stone" [link is to product info at Amazon], a wonderful medical novel by Dr. Abraham Verghese about twin brother surgeons practicing in Addis Ababa. Apparently you are not alone in finding that it worked.

But infection control & single use didn't close that option down ... nothing would be easier than packaging sterile bluestone crystals for one-time use.

Rather, Congress sold out to lobbyists -- turning today's FDA into a revolving door of, for, and by the pharmaceutical industry.

A very cool trick the FDA pulled was to rule that decades-old and centuries-old traditional remedies are considered "new" medicines which can't be sold until multi-million dollar testing is completed. Since nobody can patent traditional remedies and make large profits from them, they know that the testing will never happen ... so they can just pull all traditional medicines off the market. The primary purpose of today's FDA is to grow the profits of big pharma/mega-corps, and this cute little trick was a stroke of genius, because if the FDA really cared about medical costs, they'd simply do the tests on traditional medicines themselves or give a university a grant to do it.


Ted Mooney,
Teds signature
Ted Mooney, P.E. RET
Pine Beach, New Jersey

May 11, 2010

My knowledge comes from the Ancient Black Cherokee Medicine Women- I have used the blue stone soaking treatment as a measure to extract food poisoning from my system. I had taken a journey in the sushi land in Vancouver and Calgary Canada. I added insult to the injury and ate or should I say pigged out! on fried turkey using peanut oil. I thought I was going to die- I didn't know what to do, all of a sudden, the voice of my mother emerged - "Soak your feet in blue stone water, as hot as you can stand it:-While soaking your feet simultaneously drinking a icy cold glass of water (my personal addition to the treatment). After soaking for about five minutes, I regurgitated, and I was amazed as to the good feelings I felt in my stomach.

Betty Smith
Holistic Services - Georgetown, Georgia


My knowledge comes from eight brass monkeys from the ancient sacred crypts of Eqypt ... sorry, pardon the interruption, just stream of consciousness :-)

Ted Mooney,
Teds signature
Ted Mooney, P.E. RET
Pine Beach, New Jersey

August 2, 2013

! RAW honey used for wound dressing, not allowed to use in Hospitals which is probably encouraged by pharmaceuticals, because they would not be able to capture the honey market.
Doctors in New Zealand have done extensive research on the use of honey for dressing on wounds and burns with very positive results. But the pharmaceuticals will fight it all the way with their unlimited bank accounts.

Rino Manarin
interested party - Vancouver BC, Canada

Copper sulfate powder

July 12, 2010

I've been searching for pure copper sulfate and came across this forum. It's interesting to see the different approaches to "old time" remedies. Some people say not to use them just (I think) on principal, but I have found that there is a lot of wisdom in some of the old ways.

Anyway, some of you say that you have found the copper sulfate at farm stores. My question is if it is pure? I've purchased several containers of Copper Sulfate only to get it home and find that there are many other ingredients that make it unsuitable for my use. Any idea where one can buy pure copper sulfate powder?

Jennifer Keys
- Walnut Grove, Missouri

Ed. note: Here is 99+% pure copper sulphate, Jennifer =>
But we are not doctors or epidemiologists and are NOT advocating whatever use you have in mind for it :-)

July 31, 2010

My gardener, a young man from Zimbabwe, was experiencing stomach pain and was sure he had an ulcer. On one of his trips home to Zimbabwe he consulted a traditional healer for help with the pain he was feeling. He was given "blue stone" and told to drink lots of water. It so happened that he was unable to drink water that day because he was sitting in a queue at the Home Affairs Office trying to sort out his passport. By evening he was vomiting blood. Two days later he died. A young, promising life snuffed out by a quack doctor!

Beryl Hook
- Johannesburg South Africa

Copper Sulfate

September 17, 2010

In Ireland bluestone has many uses. We use it for spraying potatoes, cleaning chimneys, curing animals of illness. I have used it to cure toothache. a tiny amount on cotton tip in cavity 4 seconds then rinse mouth. 10 seconds later nerve is dead.

paddy farrell
retired builder - lanesboro ireland

March 20, 2013

I use to get blue stone from this old hippie dude about 10 years ago. He gave it to me told me to put it on an exposed nerve in a tooth said it would kill the nerve. It worked like a dream But I got health insurance so I didn't need home cures anymore so ended up losing touch with him. Now I have no health insurance and I have a tooth that is killing me. They were little blue rocks -- anyone know where to get them anymore?

Velvet Rose Aguilar
- Portland Oregon usa

Forgotten Ellis Island (DVD)

November 30, 2010

My grandmother tells the story of my grandfather having eye problems (some infection?) in about 1910. As a young couple they came to Barnes Hospital in St Louis for treatment for several weeks. "They touched his eyes with the blue stone and he couldn't see". He was virtually blind for about a year. He eventually regained some of his sight but probably was near legally blind for life.

I have been looking for a reference for years.

He was a farmer and lost the farm in the depression. Later worked driving a team of horses for road work in central IL. When oil was produced in the area, he started driving an oil truck, and eventually a gas delivery truck for farmers in the area.

Tonight on a PBS special, "Forgotten Ellis Island" =>
they described treating an eye infection with copper sulphate, a VERY painful treatment. Quotes from several in the show mentioned using the "blue stone".

Dave Wicks
- St Louis Missouri USA

June 13, 2011

Just recently came across a recipe from my great-grandmother for "green salve". We still have a small amount of this in a jar and still use it for 'drawing out' deep splinters. It REALLY works. The recipe calls for a tablespoon of blue stone as well as a teaspoon of VERTIGREASE. From this blog, I think I may be able to find the blue stone at the farm store, but has anyone ever heard of where to buy vertigrease? Would love to make more of this remarkable home remedy!

Sherry Spence
- Lubbock, Texas

July 14, 2011

I do believe you're talking about verdigris:

Interesting discussion.

Mary Zupan
- Los Angeles, California

Styptic Powder

July 6, 2011

Oddly, copper sulfate is one of the ingredients of the styptic powder, Kwik Stop, which is widely used to stop superficial bleeding in animals--for example, due to nail/claw clipping that nicks a vein. I believe that one of my pet birds experiences a rare bad side effect from this product, and I was searching for information on the side effects of its components in order to see what the culprit (if any) might be when I came across this web site. Very interesting! Carry on!

Kathleen Gallagher
- Greenbelt, Maryland, U.S.A.

July 19, 2011

You may be interested that copper sulphate is used in a method of etching in printmaking. You paint a piece of metal e.g. zinc, with a resist then when the resist is dry cut into it with a sharp tool. Then you put the plate into a bath of copper sulphate and salt which cuts into the exposed metal (etches) and then you print the up the plate. So I would say treat copper sulphate with care....!

B. Connolly
- Ireland

August 3, 2011

Blue stone can be purchased in small quantities, in powder or cut form from the Penn Herb Company & they have a great website. I just ordered 1 oz. powder for $1.95 for my husband. He plans to inject it into chicken eggs & put them back on a certain nest, to discourage our cats from eating them. It will just make them sick, he says, and he knows from seeing his Daddy do it. Very interesting discussion. Thanks, all.

Kat Mullally
- Lineville, Alabama, USA

November 2, 2012

A. I grew up using blue stone on horses that came down with colic. Wet a little in a small lid from a jar and hold it under the horse's stomach (naval area) until they moved away. Do this several times and the horse would eventually have a bowel movement, curing the colic.

Doug Greathouse
- Algoa, Texas

January 28, 2013

Q. What is bluestone, and can I give it to my husband who has a sex problem (too much libido)?

Please help, or give me advice on something else.

Thank you

Lindie B [last name deleted for privacy by Editor]
- Mpumalanga witbank, South Africa

January 28, 2013

A. Bluestone is inedible, Lindie! Although it would probably make him nauseous enough to lose interest, it could do serious damage or kill him; PLEASE don't give it to him unless you are trying to poison him.

Sorry, "something else" to try is not within my area of knowledge. But FYI, we have a thread on-line here from a British fabricator inquiring about the best way to polish the stainless steel on his line of high security chastity belts for men. If you maintain control of the key, the problem is certainly solved, although perhaps not much to your husband's liking :-)


Ted Mooney,
Teds signature
Ted Mooney, P.E. RET
Pine Beach, New Jersey

August 8, 2013

Q. I'm very interested in getting some blue stone crystal rocks. I grew up with sand sores and my grandmother put bluestone in water then rubbed it all over me and it healed. My mother loved her for that because when I scratched sores they would make more but my Grandmother came to the rescue. RIP Grandma.

Kimestry Jackson
- Marietta, Georgia, USA

July 2, 2014

thumbs up sign  Ted Mooney, you keep cracking me up. Fun posting to read; learned a lot too.

Marly French
- Byrnes Mill, Missouri

July 2014

Thanks very much Marly. I'm from the electroplating industry and our "patron saint" Michael Faraday once remarked:

"Though to all true philosophers, science and nature will have charms innumerable in every dress, yet I am sorry to say that the generality of mankind cannot accompany us one short hour unless the path is strewn with flowers."

I am no philosopher, just part of that generality of mankind -- so anything this site can do to amuse the readers and myself is embraced. Thanks for patronizing this site, thus helping me hold the world's best job :-)


Ted Mooney,
Teds signature
Ted Mooney, P.E. RET
Pine Beach, New Jersey

October 17, 2014

! I bought a bag of it at a Chinese herb shop. They said the Asians still use it; they rub it on their skin for various things: it's good for wrinkles, it tightens skin, it's antibacterial and I use it for warts. I didn't know what it was at first but I bought it because it was so pretty and then she told me what it was! :)

I read they use it for nail fungus with horses. I soaked my feet in it and my toenails turned like green glass and it killed all the fungus. It kind of burns but it's very effective. You can scrape a mole off and rub the bloody spot with it and it will usually get rid of it. It's like it burns it, burns it off. I do believe it should be used very sparingly. It makes your toenails very pretty though, haha. :))

I had a mole I wanted to burn off but ended up scraping it and then I thought I'd rub it with copper sulfate and it was like it burned it. It turns it bluish-black and it just kills everything there and forms a good scab. To the people wondering about toothache; Cloves. Used like chewing tobacco but you can swallow it. The active ingredient kills and removes all plaque and can heal small cavities.

- Newcastle Washington United States

February 23, 2015

! As a boy growing up in Jamaica, I always had cuts and scrapes. My uncle kept a regular supply of "BLUE STONE" which he would crumble a pinch on the wound, and then send me to swill off excess under the tap. That's when all hell broke loose as my screaming could be heard all around the village -- but within a few days, wound was almost healed.

I can vouch for "BLUE STONE"


Hugh Watkis
Retired Fitter - St. Ann- Jamaica

March 25, 2015

I'm 64 and last year (2014) I developed a Bella Carsinoma on my ear and confirmed by my doctor. To remove is was to do surgery with a "flap technique." It was the about half the size of a dime.

I have used Blue Stone for 30 years for ulcers.

I figured why not give it a try for this. First I applied a product called Freeze in a small yellow bottle used for wart removal. My objective was to create a paste for the Blue Stone. After I applied it, I dabbed a little more Blue Stone onto the spot. Then I applied a band-aid. Remarkably, it removed the cancer and healed beautifully.

It took about 14 days to do the job. I cleaned the spot every few days with hydroperoxide. One application did it. It turned brown and crusted over in about 24 hours. I suppose that was a scab forming.

Maybe I was lucky, but it sure worked and I did not have to have surgery.

stephen Cheek
- Kosciusko, Mississippi USA

Ed. note: Again, the editor of this site is a plating equipment engineer, not a doctor. We are unqualified to encourage or discourage the ideas you read here. Our editorial policy is simply that if a posting doesn't violate our proscriptions against advertising, spamming, ad hominem attacks, or profanity, we post it; we don't censor people or the marketplace of ideas.

April 2, 2015

! I use Blue Stone in a mix to treat rain scauld, insect bites, QLD itch, on horses. Blue stone with olive oil, swift, Vetadine, Sulen Blue can be added as well. You wash horse, apply mix like a shampoo, scrub all over, leave on for 20 min, and then rinse off. Great for getting coat ready for showing. Also feed garlic in feed to prevent insects and help coat shine. Sorry white horses turn green! Have to dilute and use more frequently on white horses.

Pekita Pryor
- goldcoast QLD Australia

September 8, 2016 -- this entry appended to this thread by editor in lieu of spawning a duplicative thread

Q. Sir,

Bleach/chlorine keeps coming up on my search for a killer/disinfectant/sterilizer of bacteria/fungus/viruses.

Particularly I'm seeking to eradicate the fungus that has cultured under and on my nails.

Basically I'm at a point of information overload. And my objective is desperate. Living with "crusty" nails is no fun.

There are worst things that I can think of however. However, my concern is my toe nails. I want them to return to a healthy equilibrium.

Aside from all the possible health concerns associated with my condition is beyond my inquiry. All I ask is your thoughtful analysis of what product/concentration of bleach/other, etc., per se, would be a possible positive direction for solution.

I accept the inherent risks that this inquiry entails. All I ask is for your sensible contribution to what "does" in theory kill such fungus, whether in the body or outside the body, directly or indirectly (e.g. hospital equipment).

Thank you and may you be find inspiration to reply what could possibly be the answer, even it be informative in general terms.

Amber Marty
- Hilo, Hawaii, USA

September 2016

A. Hi Amber. We appended your inquiry to a thread about blue stone (copper sulphate) because it addressed your issue in the tone you seek.

I have a couple of occasionally white toe nails which respond overnight to simple over the counter application of antibiotics like Bacitracin or Neosporin (apparently mild cases are sometimes bacteria rather than fungus?). As a teenager with athlete's foot I recklessly soaked in rather strong hot bleach and solved the problem, so I think bleach is pretty good at killing fungus, although they say toenail fungus is tougher because the nails protect it. I can't see your objection to the pharmaceutical industry's solution of ingesting a $14 pill each day for 12 weeks and seeing whether it works out and what side effects hit you :-)

As you probably discovered, there are countless youtube videos on the subject of bleach as a fungus treatment.

Luck and Regards,

pic of Ted Mooney
Teds signature
Ted Mooney, P.E. RET
Pine Beach, New Jersey
Striving to live "Aloha"

September 29, 2016

thumbs up signEureka!! I had been searching for what Bluestone is for a number of years. I inherited a piece in a jar that was my grandmothers. (She died in 1981.) I was told it was medicinal & poisonous. My mom's handwritten note said it "only eats sore part,not healthy tissue". My mom told me you rub it on a sore.
I had been looking up copper sulfate for an unrelated reason & am so happy that I stumbled across this page.
Thank you everyone for the insights!

Sandra Stocks
- Cincinnati Ohio, USA

July 19, 2017

Q. When I was a little girl ever time I got in the tub to take a bath when I would get out I would itch all over my grandmother would use a pail with water and place this big blue Stone in It water would turn blue and she would wash me down. I would like to find some blue Stone, where can I find It?

Annet Williams
- Augusta Georgia

July 2017

A. Hi Annet. I am not advocating your grandmother's idea, but bluestone is copper-sulphate pentahydrate (CuSO4.5H20) and it's available everywhere as a root and algae killer. Every pool store and farm store has it, and it's available on line too.


pic of Ted Mooney
Ted Mooney, P.E. RET
Pine Beach, New Jersey
Striving to live "Aloha"

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