Mountain Valley Spring Water by Mountain Valley is a still natural spring water originating from the Ouachita Mountains in the US state of Arkansas. The water comes from a protected spring surrounded by forest near the city of Hot Springs. According to the producer its natural cycle lasts approximately 3,500 to 4,000 years. The water enters underground granite-lined aquifers and then returns to the surface through layers of limestone, quartz, and marble. During this process it naturally acquires calcium, magnesium, potassium, and other dissolved substances. According to the producer’s analysis it contains approximately 67 milligrams of calcium, 7.2 milligrams of magnesium, and 1.4 milligrams of potassium per liter. Its total dissolved solids content is approximately 220 milligrams per liter. Its pH ranges from approximately 7.2 to 7.4 which makes the water mildly alkaline. The minerals give it a mild, clean, and rounded taste without pronounced salinity. It is bottled near the source without the subsequent addition of minerals. Although it has a noticeable natural mineral content it is classified as spring water rather than mineral water under US regulations because it contains fewer than 250 milligrams of dissolved solids per liter. It is traditionally packaged in distinctive green glass bottles which help preserve its neutral flavor.