A key factor in ensuring the quality of precision castings is the quality of the slurry – the ceramic that covers patterns to create investment casting molds. To begin, the proper slurry formula must be used for the application, and it must be mixed in the appropriate manner. Once the slurry is made, it will have a finite life, after which it will not perform optimally. A variety of factors can degrade the slurry, especially water loss, which changes the viscosity and can compromise the mold strength. Experience and advanced capabilities are necessary to ensure that the slurry, the molds and the castings are optimal.