Possible resources are minerals which are thought to exist based on limited locational knowledge and exploration, thus the quantity and quality is known with the least confidence of any of the categories. Possible resources can sometimes be referred to as hypothetical or speculative. Hypothetical resources are those in regions where mining/drilling (or other extraction) takes place but haven't yet been discovered, but they are anticipated to exist due to particular geological conditions similar to those where they have been seen to occur before. Speculative resources are predicted resources in regions where no extraction currently takes place.