Often refered to as wine diamonds, these crystals are often processed and are used as cream of tartar in ordinary kitchens. Once the wine has settled and is clear then the finning is done if needed. Tartrates dropped, wine aged, and balanced. Now is the time for filtering. Filtering takes place in many different ways.
Some wines are ready to bottle just from racking and aging.
Others require D.E. Filtering or pad filtering or micron filtering. Diatomaceous Earth filters are very gentle and work on a sieve principle. Filter pads work on absorption, and micron filters, which filter out extremely small particles, work on the sieve principle. These last filters are also known as police filters because they screen bacteria and yeast cells. It is a long time after the last grape arrives in the fall and the time when the wine ready for bottling.