The Stone Detective – The Case of Mistaken Identity
Dr. Frederick M. Hueston, PhD
The aroma of fried eggs and coffee hit me as I walked through the creaky doors of my favorite greasy spoon. Flo had her eyes on the door and probably saw my ole Woody pull up outside. She was already pouring a morning cup of joe for me. I accepted the fresh cup with a nod of thanks, proceeded to my regular booth and sat down on the worn vinyl cushions. But when I turned to speak to the Admiral, who was usually sitting at the table next to mine, I realized something was wrong.
The man in front of me was wearing a worn-out jacket that looked a lot like the Admiral’s, and he was sitting in the exact spot he would normally find comfort. Those who know my stories will remember that the Admiral always sat in that same spot every morning. I almost said, “Good morning, Admiral,” and realized right away it wasn’t him. I looked at Flo and motioned for her to come over. I then asked her if she had heard from our usual customer. When we looked at each other, her answer was quick and unsettling. “No,” she said, and her worry was clear. “I hope he’s all right.”
Just as I was about to take a sip of my coffee, the Admiral walked into the diner. This sent a wave of confusion through the room. He looked at the strange person sitting on his favorite stool with a mix of confusion and irritation on his face. He didn’t seem to mind, so he sat down next to me at the other end of the booth and greeted me with a big, “Good morning.” True to his nature, the Admiral started telling me stories right away.
I had no idea that this case of mistaken identity would soon tie into my next case.
I finished my cup of joe and started to say goodbye to Flo and the Admiral when my phone rang. The voice on the other end had a gravely tone grated like a rusty hinge struggling against the weight of time. He went into a rant about how he was sold a marble countertop and that the technician who came out to polish it said it wasn’t marble. “I got ripped off!” He screamed at me. I just listened and he went on and on about how contractors are always ripping people off, etcetera, etcetera, etcetera. After he finished voicing his dissatisfaction, I asked him what the technician said. “He told me it wasn’t marble, but some kind of Duceamite, Toldamite, or something that sounds like that.” I said it sounds like Dolomite. “Yes, that’s it!” he said. I asked if he could send me a pic and then I might be able to identify it. I gave him my email and decided to stay for one more cup of joe and to probably hear a repeat of the Admiral’s adventures. When I was done, I said my farewells and headed back to my office.
I sat down at my desk and immediately opened my email. Sure enough, there was the email I was expecting from Mr. Foghorn. The email was nothing more than a rant repeating how he had been ripped off. I downloaded the pic, and sure enough, without a doubt it was dolomite. Instead of calling him to tell him that he indeed had a type of marble, and that although it is a type of marble, it’s known more specifically as a dolomitic marble. It just so happens that I just wrote a brief description of the difference between a calcium-based marble and a dolomitic marble. So, I emailed him the following:
Dolomite and marble are both natural stones that have similar appearances, which can make it challenging to differentiate between them. However, there are a few key characteristics that can help you tell the difference between dolomite and marble:
Composition: Dolomite is primarily composed of calcium magnesium carbonate (CaMg (CO3)2), while marble is composed of calcium carbonate (CaCO3). The presence of magnesium in dolomite gives it a slightly different chemical composition than marble.
Hardness: Marble is a relatively soft stone with a hardness of around 3-4 on the Mohs scale, which means it can be easily scratched with a knife. Dolomite, on the other hand, is slightly harder with a hardness of around 3.5-4.5. It can still be scratched by harder materials, but it is generally more resistant to scratches than marble.
Appearance: While both dolomite and marble can have similar colors and patterns, there are often subtle differences in their appearance. Dolomite tends to have a more uniform and consistent coloration, while marble may display more pronounced veining and color variations.
Acid Reaction: Another way to differentiate dolomite from marble is by performing an acid test. Dolomite is slightly acidic and will effervesce or bubble when it comes into contact with a weak acid like vinegar. Marble, being primarily composed of calcium carbonate, is highly reactive to acids and will effervesce more vigorously.
Geological Origin: Dolomite and marble have different geological origins. Dolomite is formed through the alteration of limestone or lime-rich sediments under high temperature and pressure. Marble, on the other hand, is formed through the recrystallization of limestone under similar conditions.
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Left: Dolomite tends to have a more uniform and consistent color. Right: Marble may display more pronounced veining and often has color variations. |
It’s important to note that professional analysis and testing by a geologist or a stone specialist is the most accurate way to determine the exact composition of a stone. If you are unsure about the type of stone you have, it is recommended to seek expert advice to ensure accuracy. I AM that expert.
Finally, I assured him that he hadn’t ripped off. As for the technician brought in to polish his dolomite, I’m sure that if allowed, he would have something to say to Mr. Squeaky Hinge-Foghorn as well, and probably less politely phrased than my response. Another case solved.
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. Send your comments to fhueston@stoneforensics.com.