Pearls are comprised of about 90 per cent calcium carbonate, a small amount of water, and Conchiolin which is an organic protein present to bind the crystals. The pearl is composed of calcium carbonate. This chemical can dissolve in a weak acid. Vinegar is composed of nearly five to seven per cent, which is the concentration that is required for calcium carbonate dissolution. The calcium carbonate crystals are transformed by the acetic acid into calcium. The byproducts of this reaction also give rise to carbon dioxide and water. A little bit of vinegar dripped onto the pearls will form bubbles on them. If the eggshell is kept inside the vinegar, the eggshell will also be destroyed.
The pearls are known to consist of a material called nacre. This material is synthesized by calcium carbonate, marble, and limestone. Nacre constitutes aragonite and calcite. The pearl is made of several plates of this substance packed together by Conchiolin. According to the chemical makeup of pearls, it can dissolve in any acidic solution. Pearls can dissolve in vinegar, orange juice, and even in wine. The pearl will start dissolving due to the acetic acid when it is dropped into the vinegar. The duration of the melting is based on many features like temperature, surface area of the pearl, and the strength of acidity exhibited by the vinegar.
The pearl is authenticated in the proper way by vinegar. The pearl is tested by checking whether it reacts with the vinegar or not, and it is done by placing a drop of vinegar on the pearl. If the pearl fizzes with the acetic acid reaction, it is said to be real. The vinegar will not react with the pearls that are not real. The pearl merchants often warn the customers not to put them in vinegar just for the reason that the calcium carbonate will neutralize the acetic acid in the vinegar.