Diamond Mountain District is an

American Viticultural Area An American Viticultural Area (AVA) is a designated wine grape-growing region in the United States, providing an official appellation for the mutual benefit of winery, wineries and consumers. Winemakers frequently want their consumers to know abo ...

located in

California California () is a U.S. state, state in the Western United States that lies on the West Coast of the United States, Pacific Coast. It borders Oregon to the north, Nevada and Arizona to the east, and shares Mexico–United States border, an ...

Mayacamas Mountains The Mayacamas Mountains are located in northwestern California in the United States. The mountain range is part of the Northern Inner Coast Ranges, of the California Coast Ranges System. Geography The Mayacamas Mountains are located south of th ...

in the northwest portion of the

Napa Valley AVA Napa Valley is an American Viticultural Area (AVA) in Napa County, California. The area was established by the Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) on February 27, 1981, after a 1978 petition submitted by the Napa Valley Vin ...

. The

appellation An appellation is a legally defined and protected geographical indication used to identify where the ingredients of a food or beverage originated, most often used for the origin of wine grapes. Restrictions other than geographical boundaries, s ...

sits at a higher elevation than most of

Napa Valley Napa Valley is an American Viticultural Area (AVA) in Napa County, California. The area was established by the Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) on February 27, 1981, after a 1978 petition submitted by the Napa Valley Vin ...

's wine region, resulting in less cool fog coming in from

San Pablo Bay San Pablo Bay is a tidal estuary that forms the northern extension of the San Francisco Bay in the East Bay and North Bay regions of the San Francisco Bay Area in northern California. Most of the Bay is shallow; however, there is a deep wate ...

, and more direct exposure to

sunlight Sunlight is the portion of the electromagnetic radiation which is emitted by the Sun (i.e. solar radiation) and received by the Earth, in particular the visible spectrum, visible light perceptible to the human eye as well as invisible infrare ...

. The soil of this AVA is

volcanic A volcano is commonly defined as a vent or fissure in the crust of a planetary-mass object, such as Earth, that allows hot lava, volcanic ash, and gases to escape from a magma chamber below the surface. On Earth, volcanoes are most often fo ...

and very

porous Porosity or void fraction is a measure of the void (i.e. "empty") spaces in a material, and is a fraction of the volume of voids over the total volume, between 0 and 1, or as a percentage between 0% and 100%. Strictly speaking, some tests measure ...

which allows it to cool down quickly despite the increased sunlight.

Geography and climate

The entire AVA is over above sea level, which helps to cool it compared to the nearby valley floor appellations. The soil of the Diamond Mountain District is volcanic, including the small bits of

volcanic glass Volcanic glass is the amorphous (uncrystallized) product of rapidly cooling magma. Like all types of glass, it is a state of matter intermediate between the closely packed, highly ordered array of a crystal and the highly disordered array of liqu ...

that give the area its name. The AVA is defined by the Napa- Sonoma county line on the west, Petrified Forest Road on the north, the 400 foot line of altitude running parallel to Route 29 on the east, and the Spring Mountain District to the south. This puts the southern part of the city of

Calistoga, California Calistoga (Wappo language, Wappo: ''Nilektsonoma'') is a city in Napa County, California, United States. Located in the North Bay (San Francisco Bay Area), North Bay region of the San Francisco Bay Area, the city had a population of 5,228 as of ...

in the appellation, with the northern part being in the

Calistoga AVA Calistoga is an American Viticultural Area located in the northern portion of California's Napa Valley AVA. The appellation is distinguished by its volcanic soil, high temperatures up to during the day, and cool nights during the growing season ...

since 2010.

History

Diamond Mountain District's history as a winegrowing region dates back to 1868, when the first vines were planted by Jacob Schram on a tract of land he purchased on the Napa side of the mountain. By 1892, his holdings had expanded to 100 acres, including underground cellars for aging and storing wine. His name has continued in the property, now known as

Schramsberg Vineyards Schramsberg Vineyards is a winery located in Calistoga, California in the Napa Valley region. The vineyard, which was founded in 1862 by the German immigrant Jacob Schram, produces a series of sparkling wines using the same method as champagne. ...

Controversy

When the AVA was proposed in 1999, a request for public comments was published in the Federal Register. One winery, Diamond Mountain Vineyards, objected to the western border ending on the Napa-Sonoma county line, as it would split their property in half. Their objections extended the public comment period by several months. Ultimately, the decision was to keep the boundary on the Napa-Sonoma line. Additionally, as originally proposed, the AVA would have been called the "Diamond Mountain AVA," but since the bulk of Diamond Mountain, and indeed, its peak, are in Sonoma County, the AVA was renamed.

References

External links

{{Authority control American Viticultural Areas of Napa Valley, California 2001 establishments in California