Black diamond is located in King county Washington with a geographic area of 6.6 square miles. The total population in Black diamond is 4,703 with 49.2% male and 50.8% female. Children under age 5 represent 5.2% of the population, under age 18 equal 19.8% of the population and over age 65 is 16.9% of the population. The median household income is $111,250, per capita income is $51,018. There are a total of 1,859 housing units with 84.7% owner occupied. Education includes 14.0% of residents that are high school graduates and 43.0% with a bachelor's degree or higher. The average temperature in Black diamond in the summer is 61 degrees, and in the winter 42 degrees.
