Sparkle is an unincorporated community

Unincorporated area

In law, an unincorporated area is a region of land that is not a part of any municipality.To "incorporate" in this context means to form a municipal corporation, a city, town, or village with its own government. An unincorporated community is usually not subject to or taxed by a municipal government...

 in Contra Costa County

Contra Costa County, California

Contra Costa County is a primarily suburban county in the San Francisco Bay Area of the U.S. state of California. As of the 2010 census, it had a population of 1,049,025...

, California

California

California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...

, United States

United States

The United States of America is a federal constitutional republic comprising fifty states and a federal district...

. It is on the former route of the Sacramento Northern Railroad, now replaced by elevated BART tracks 2 miles (3.2 km)north of downtown Walnut Creek

Walnut Creek, California

Walnut Creek is an incorporated city located east of the city of Oakland. It lies in the East Bay region of the San Francisco Bay Area. While not as large as neighboring Concord, Walnut Creek serves as the business and entertainment hub for the neighboring cities within central Contra Costa...

, at an elevation of 85 feet (26 m). It reputedly got its name from a discharge effect on a tight curve of the electrified line of the Sacramento Northern Railroad. It is a county island

County island

A county island is an unincorporated area within a county, usually, but not always, surrounded on all sides by another incorporated area, such as a city. On maps, these geopolitical anomalies will form jagged or complex borders and 'holes' in the city limits...

 like nearby Waldon

Waldon, California

Waldon is a former census-designated place in Contra Costa County, California, United States. The population was 5,133 at the 2000 census. The Pittsburg/Bay Point – SFO Line line of the Bay Area Rapid Transit system serves the surrounding area using the Pleasant Hill/Contra Costa Centre Station...

 and is surrounded by Walnut Creek

Walnut Creek, California

Walnut Creek is an incorporated city located east of the city of Oakland. It lies in the East Bay region of the San Francisco Bay Area. While not as large as neighboring Concord, Walnut Creek serves as the business and entertainment hub for the neighboring cities within central Contra Costa...

 and other incorporated cities. The ZIP Code is 94597. The community is inside area code 925

Area code 925

In the North American Numbering Plan , area code 925 is an area code that covers the inland portions of the East Bay counties of Alameda and Contra Costa in northern California....

.