Have you ever noticed tiny little crystals on a cork or bottom of your wine bottle? What are these critters? Should you be concerned about them? Do you need to return the bottle to your retailer for a refund?
No! More than likely those are “wine diamonds”.
These tasteless crystals are the by-product of potassium bitartrate, or tartaric acid (think Cream of Tartar), the most prevalent acid found in wine. Acids such as tartaric, malic, lactic, etc., are important in giving that freshness to wine that we all enjoy.
Although more commonly found in white wines, wine diamonds can also be found in red. Simply put, they indicate that the winemaker may have intentionally chosen to skip certain steps (such as cold stabilization) which tend to reduce tartaric acid. This is typically a conscious decision based on the chemistry of the wine during the winemaking process. Drink on!
