In this type of contract, the elements are not specifically written or expressed. In fact, this type of contract is used as a remedy in a situation when one party to the quasi-agreement received unjust enrichment resulting from not paying for a product or service rendered.
A Drupe is a single fleshy fruit with a hard stone which contains the single seed. This is a Cherry (Prunus avium). Other fruits of this type are: Apricot (Prunus armeniaca), Plum (Prunus x domestica), Coconut (Cocos nucifera), Olive (Olea europaea), Peach (Prunus persica), Sloe (Prunus spinosa).
Left: Small, shriveled fruits of the date palm (Phoenix dactylifera) that were pruned from the bunches to allow for optimal development of the crop. Right: Mature, pollinated dates that were allowed to ripen on the tree. The date fruit (technically called a drupe) contains a hard, seed-bearing pit or endocarp.