Simanaitis Says

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THIS ALL STARTED yesterday with private investigator George Valentine (of SiriusXM “Radio Classics” Let George Do It) reading Pliny’s account of Cleopatra downing a pearl dissolved in vinegar. Today in Part 2, there’s a naysayer, some art, some science, and even a bit of philosophy.

According to naysayer Peter Tomory’s “Cleopatra, Pearls and Extravagance: Tiepolo’s Banquet of Cleopatra, “There is, of course, no vinegar that can dissolve pearls, so it is quite clear that Cleopatra swallowed the pearl, knowing she could get it back one way or another!”


The Berlin Kleopatra, a Roman sculpture of Cleopatra created mid-1st century B.C., discovered in an Italian villa along the Via Appia and now located in the Altes Museum, Berlin. Image by Lous le Grand.

Artists inspired by Cleopatra’s quaffing are also a Tomory topic. He cites Giovanni Tiepolo, Jacob Jordaens, Gérard de Lairesse, and Jan de Bray (who painted family members and himself in two versions) as those recognizing the artistic aspects of what was essentially a culinary bet between Cleopatra and Mark Antony.

The Banquet of Cleopatra, 1744, by Giovanni Battista Tiepolo, 1696–1770, painter and printmaker in the Republic of Venice.

The science of Cleopatra’s quaffing is discussed in various sources. is concise on the matter: “Pearls dissolve in vinegar!!! Chemically, there’s nothing strange about it. Pearls are basically Calcium carbonate (CaCO3), like marble and lime stone. We know that carbonates and bicarbonates react with acids liberating CO2 forming the corresponding salts. Vinegar is acetic acid (10 percent), so pearls will naturally dissolve….”

Pearl dissolution in acetic acid. Image from

On the other hand, marble doesn’t exactly disappear if vinegar is spilled on it. Chemical reactions vary with time, depending on a host of parameters.

Berthold Ullman brings up a philosophical aspect: “Pearls don’t dissolve instantly like pills. But I don’t think that is of much importance. I am concerned with a mystery so slight that no one seems to have thought of it but me…. I ask myself this question: Why did people dissolve, or try to dissolve pearls in vinegar?”

He likens it to other extravagances, like lighting a cigar with a ten-dollar bill or dining on peacock. “Take off their feathers, which you cannot eat,… and they are just ordinary fowl; they are, as a matter of fact, tougher.”

The Meeting of Antony and Cleopatra, 1885, by Lawrence Alma-Tadema.

And More Science. Ullman writes, “Until a short time ago, my attempts at experimentation have been desultory and inconclusive. It obviously took a long time for pearls to dissolve in cold vinegar. Still it was possible to see in my experiments that something was happening, as bubbles (of carbolic acid) were rising to the top.”

“I hasten to add,” Ullman notes, “they were fresh-water pearls of irregular shape and of no value in the pearl market.”

He tried heating the vinegar to promote the reaction: “When I boiled a pearl for 33 minutes, the vinegar boiled off while I was reading a detective story. I can still smell that vinegar.”

Professor Ullman then turned to colleagues in the Chemistry Department: “After 200 minutes, the boiled whole pearls were 92-percent and 88-percent dissolved [in 8-percent and 5-percent acetic acid, respectively].”

If first pulverized with a pestle and mortar, “no doubt the method the ancients used,” cold ascetic acid did the trick in ten minutes.

“Perhaps,” Ullman writes, “this paper should be called ‘Cleopatra’s Vinegar’ instead of ‘Cleopatra’s Pearls,’ but for obvious reasons the latter is preferable.”

And more entertaining. Thanks, Professor. ds

© Dennis Simanaitis,, 2018


  1. Gordon Craig
    September 6, 2018

    Given the off gassing is CO2, wouldn’t Cleopatra have poisoned herself, oxygen deprivation in the short or more certainly the long term? Also, whatever mineral content/residue left behind would surely play havoc with her kidneys, she would be making her own pearls, ugh.

  2. Bob DuBois
    September 6, 2018

    You have mistakenly identified the bubbles rising from the pearl/vinegar reaction as “carbolic acid”. Carbolic acid is an organic compound, formula C6H5OH, which is essentially a benzene ring with one hydrogen atom replaced with a hydroxyl(OH) group. Phenol has a sweet odor, and has the bad effect of numbing the skin so that you can’t feel how it is absorbing into the skin and burning it badly. As a retired chemist who worked for a company that produced phenol. I had a lot of experiences with it’s effect on skin!

  3. Bob DuBois
    September 6, 2018

    I forgot to mention that carbolic acid is the commercial name for phenol.

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