Diamond: Chemically these are Potassium Tartrate crystals, at the bottom of the wine bottles. Wine with excessive levels of tartaric acid tends to exhibit these diamond/ sugar like structures during aging. The best way to get rid of them is to cold crash (24 hours at 4o C) and then bottle. It is sediment in the bottle and does not affect the sensory perception in any other adverse way. One of the reasons expensive wine bottles have a dimpled base is that these crystals are stuck to the dimple structure at the bottom and are not poured out in the wine glass.