[5] The Crystal post office, with ZIP code 48818, serves the northern portion of Crystal Township as well as portions of southern Ferris Township.

[1] The township is drained mainly by Fish Creek, which crosses the township from west to southeast and is a tributary of the Maple River, part of the Grand River watershed flowing to Lake Michigan.

The northeast corner of the township is drained by Carpenter Creek, a tributary of the Pine River, part of the watershed flowing to Saginaw Bay on Lake Huron.

As of the census[3] of 2000, there were 2,824 people, 1,097 households, and 770 families residing in the township.

24.0% of all households were made up of individuals, and 9.2% had someone living alone who was 65 years of age or older.