This style of wine is characterised by its dark colour, rich texture, and coffee-caramel flavours. Like other Madeiras made from noble grape varieties, the Malvasia grape used in Malmsey production has naturally high levels of acidity in the wine, which balances with the high sugar levels so the wines do not taste cloyingly sweet. Sercial is nearly fermented completely dry, with very little residual sugar (0.5 to 1.5° on the Baumé scale, or 9-27 g/L). This style of wine is characterised by high-toned colours, almond flavours, and high acidity. Verdelho has its fermentation halted a little earlier than Sercial, when its sugars are between 1.5 and 2.5° Baumé (27-45 g/L). This style of wine is characterized by smokey notes and high acidity. A fifth noble grape, Terrantez, almost became extinct on the island but has been making a comeback. Its style ranges in sweetness from that of Verdelho to that of Bual, never being quite as dry as Sercial nor quite as sweet as Malvasia. Other labelling Wines made from at least 85% of the noble varieties of Sercial, Verdelho, Bual, and Malvasia are usually labelled based on the amount of time they were aged: Colheita or Harvest – This style includes wines from a single vintage, but aged for a shorter period than true Vintage Madeira. The wine can be labelled with a vintage date but includes the word colheita on it. Colheita must be a minimum of five years of age before being bottled and may be bottled any time after that. Effectively, most wineries would drop the word Colheita once bottling a wine at over 19 years of age because it is entitled to be referred to as vintage once it is 20 years of age. At that point, the wine can command a higher price than if it were still to be bottled as Colheita. This differs from Colheita Port which is a minimum of seven years of age before bottling. Extra Reserve (over 15 years) – This style is rare to produce, with many producers extending the aging to 20 years for a vintage or producing a colheita. It is richer in style than a Special Reserve Madeira. Reserve (five years) – This is the minimum amount of aging a wine labelled with one of the noble varieties are permitted to have. Special Reserve (10 years) – At this point, the wines are often aged