Frederick M. Hueston, PhD

It was one of those odd mornings. I woke up early, got dressed and was headed out the door when an email popped up on my phone. Rather than read it on my phone, I walked back to my desk to read it on my laptop.

I have gotten a lot of unusual questions over the years, but this one was especially odd. Intrigued, I called the lady who had sent the email. She started the conversation in tears. I could hardly understand what she was saying since she was sobbing out every word. As near as I could understand, she was having her marble floor honed and polished, and her little 7-year-old started eating the slurry from the floor. Why she contacted me instead of the emergency room, I have no idea. (I may be called the stone doctor, but not the medical kind.) My mom used to say my son’s a doctor – but not the kind that helps people – LOL!

Anyhow, the lady with the slurry-slurping kid was really concerned. I asked if the contractor was still there, and if so, could I speak with him.  She said, “Yes, he is right here, and very concerned as well!” I asked him if he was using any chemicals when honing. He told me no, it was just diamond abrasives and water. “Great!” I said. Now, I wasn’t about to give out medical advice, but I told the concerned mom that she might want to take her little boy to the ER, just to be sure.  I then went on to explain that marble is nothing more than calcium carbonate. I added that it is used in antacids, etcetera, and should be safe. Or non-toxic, at least.

I hung up the phone and within minutes the contractor called me back, all concerned. I told him that marble is used in many foods and drugs, like the aforementioned antacid. I told him I would send him an email later of some the other uses for marble. Here is the brief list:

Garden Lime

Gardeners use lime to raise the pH level of acidic soil, which can help certain plants extract nutrients from the soil. Garden lime is processed from marble. The marble is heated in a kiln, which removes the carbon dioxide from the stone, producing a form of lime called calcium oxide, or quicklime. DON’T put this lime in your coconut!

Field MarkingField Marking

In the past, lime was used to mark soccer, baseball, football, and other sports fields. Lime is very caustic, meaning it can cause discomfort or damage if the powder makes its way to a moist skin surface, such as the eyes or sweaty skin of athletes. These days, powdered marble is used as a safer alternative.

Calcium Supplements

Many farm animals require calcium for health reasons and to produce eggs, milk, etcetera. Farmers mix powdered calcium into animal feed as a supplement. These supplements are nothing more than pulverized marble.


If you take an antacid to calm your stomach, you are basically just ingesting powdered marble!


Whiting is a fine powder made of marble that is used as a brightener, filler, and even a pigment in many products. It can be used to clean glass after glazing, and to shine copper, stainless steel, and other surfaces.


One of the main ingredients for face powders and blush is pH-neutral calcium carbonate, i.e., marble dust.

Construction Aggregate

Concrete is used for road building and many other uses. Concrete mixtures require cement, water, and an aggregate, such as crushed bits of stone, gravel, or sand. Marble aggregate can be used in concrete.


Here is a little chemistry lesson. If marble is dissolved in water, it becomes alkaline, which means it increases the pH level of the water. Acid, which is low pH, can be neutralized when marble is added. Marble can be used to increase pH, so it can serve as a neutralizer in swimming pools. It is also used by water treatment plants and other chemical industries.

Your Meds

Many prescription and over the counter drugs use powdered marble as a filler. Yes, really. So the next time you need to take a pill, chances are you will be ingesting some marble.

Paint and Craft Additives

Marble powders are popular in many types of paint, as well as acrylic modeling paste, glue base gesso, and all water and oil dispersed paints.

Carbonated Beverages

Have you ever wondered why there is a tiny explosion when you pop open a can of soda? During the manufacturing process, a can is filled with CO2 (carbon dioxide) dissolved in water. When the can is sealed, the pressure causes a chemical reaction to take place, resulting in carbonic acid. The sound you hear when you open the can is caused by carbonic acid returning to the form of CO2 dissolved in water. The carbonic acid that is used in soda is derived from marble.


Sidewalk and blackboard chalk used to be made of marble, but these days, most chalk manufacturers use gypsum. 

Marcite and Plasters

Marcite, a sprayed-on coating that is applied to built-in swimming pools, contains marble dust. Many plasters also contain marble dust as their main ingredient.


Products containing marble, such as baking powder, toothpaste, dry dessert mixes, dough, and wine are for sale in your local grocery store. The next time you look at a list of ingredients and you see the word calcium, the product likely contains marble.

Carbon Capture Technology

A study by Industrial & Engineering Chemistry Research reports that one of the most promising technologies to reduce global emissions of carbon dioxide (CO2) is called calcium looping. The process involves scrubbing CO2 from flue gases by using calcium-oxide-based sorbents. Can you guess what those calcium-oxide-based sorbents are? That’s right. Waste marble powder.


Several days later I heard that the little boy was OK, and that his acid reflux had been cured.

Another case solved. Who says doctors don’t make house calls, anymore?

The Stone Detective is a fictional character created by Dr. Frederick M. Hueston, PhD, written to entertain and educate. Dr. Fred has written over 33 books on stone and tile installations, fabrication and restoration and also serves as an expert for many legal cases across the world. Fred has also been writing for the Slippery Rock for over 20 years. 

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