Glycerine jelly is a specific form of aqueous mountant, which once mastered is a quick and simple mountant to use. Glycerine jelly is a firm jelly at room temperature, but when heated to approximately 65 degrees C melts to a very runny consistency. Once allowed to cool it reforms into a firm jelly. It can be used in the same way as aqueous mountant, but has the advantage of holding a coverslip reasonably firmly in place once its temperature has dropped and its jelly state has been reformed.

A small piece of glycerine jelly will melt in the microwave after only a few seconds - or in a test tube placed in a small bath of water above 80 degrees C. Placing the finished slide in the fridge for a few minutes will hasten the setting process.

Care should be taken to ensure that any water used for washing the specimen or any fluid associated with the preparation e.g. pond water does not sufficiently dilute the glycerine jelly so that its setting properties are impaired.

Glycerine jelly mounted slides will dry back over time and the coverslips may eventually fall off the slide.

Glycerine jelly is particularly ideal for temporary mounts needed for a few weeks or so. They can be used immediately the mountant has cooled, whereas aqueous mountant preparations are not robust for a number of days.