How does the hydrometer work?
The hydrometer comes packaged in a tube/jar to be filled with water in which to float the hydrometer. The hydrometer incorporates two weighing chambers, one in air and one under water in which to place the mineral, and a stem graduated in centimeters off which readings are taken. Using the hydrometer is a simple 3 step process as shown in the illustrations. First, take a reading of the included gram weights in air to serve as a baseline weight. Secondly, take a reading of the mineral in air. Finally, take a reading of the mineral underwater. The 1st reading less the 2nd reading gives the minerals weight in air. The 1st reading less the 3rd reading gives the minerals weight in water. Then plug these two values into the SG equation to arrive at the specific gravity of the mineral.
