Lubricating grease is made by dispersing the thickener (solid phase) into the lubricating fluid (liquid phase) to form a stable product. In most cases, the thickener is the reaction product of carboxylic acid(s) and alkaline earth metal hydroxide(s), forming an organic salt, commonly referred to as a soap. In those cases, specialized reaction vessels or processes are required to effectively carry out the reaction and produce a grease with the desired properties. In other cases, the thickener is a mineral such as clay or a pre-reacted material that requires only dispersion to produce the grease. Grease can be produced by both batch and continuous processes.