Wine Diamonds

My wine has Crystals in it! Diamonds in wine?

Have you ever opened a bottle of wine to find white or red crystalline deposits stuck to the bottom of the cork, glinting at the base of the bottle, or even floating in the wine itself? Don’t panic—those crystals are called tartrates and they are simply a sign of how the wine was made. They are harmless to you and do not affect wine quality. In fact, tartrates in wine often indicate a higher quality wine. Tartrates—also affectionately called “wine diamonds” —are formed from tartaric acid, which is naturally occurring in all wines and provides structure, balance, and flavor.

What are tartrates?

Tartrate crystals, also known as wine crystals, are crystalline deposits of potassium bitartrate that can form in wine during fermentation and aging. Tartrates in wine develop when tartaric acid binds with potassium under cold conditions. Tartrate crystals in white wine have been described as having a similar appearance to shards of glass and are sometimes mistaken for unwanted or unnatural sediment.

Crystals on your wine cork

Tartaric acid dissolves differently in wine depending on the temperature. When wine is chilled below 40°F, the remaining tartaric acid binds with naturally occurring potassium, forming tartrate crystals—also known as potassium bitartrates.

Since white wines are often refrigerated before serving, you’re more likely to spot these harmless crystals in a glass of Chardonnay or Sauvignon Blanc. Some people find them a bit surprising, while others appreciate their natural beauty. Now that you know what they are, you can enjoy the little "wine diamonds" on your cork with confidence!

Why we don’t prevent crystals at our winery

Some winemakers cold stabilize their wines to prevent tartrate crystals from forming in the bottle, mainly for aesthetic reasons. But at Lost Fawn, we take a different approach. We believe cold stabilization can strip away some of the wine’s natural acidity, alter its flavor profile, and even affect its ability to age gracefully.

Our goal is to craft the best wines possible while staying true to their natural character. By skipping cold stabilization, we preserve the wine’s acidity, texture, and aromatics—letting its true flavors shine. In fact, many winemakers, sommeliers, and wine lovers see “wine diamonds” as a sign of quality, showing that the wine hasn’t been over-processed or manipulated.

If you don’t want diamonds

If you'd rather not deal with tartrate crystals—though some of us think they're kind of charming—here’s how to keep them to a minimum. Store your wine on its side at 55–60°F and chill it to 45–48°F (depending on the variety) just before serving. If those little "wine diamonds" show up anyway, no worries! Just pour the wine through a filter or cheesecloth into a decanter. Or, you can let the crystals settle at the bottom and pour the wine slowly at a slight angle. Easy as that!