The Cask is a piece of equipment used to refine goods. It takes wine and cheese and can age them to increase their quality and value.
Player can use pickaxe to take artisan goods out of cask at any stage of fermentation.
Aged items in casks can go above "gold star" quality to reach "iridium star" quality, the highest level of quality. Iridium star level quality doubles the value of an item. Different types of items take longer or slower to age. Wine takes the longest... it takes 2 seasons of aging to go from basic wine to iridium quality wine.
Casks can be placed anywhere, however they will only accept goods to refine if they are actually in the cellar.