Chalcedony to as prase. However, the term prase is also used to describe green quartz, and to a certain extent is a color-descriptor, rather than a rigorously defined mineral variety.) Blue-colored chalcedony is sometimes referred to as "blue chrysoprase" if the color is sufficiently rich, though it derives its color from the presence of copper and is largely unrelated to nickel-bearing chrysoprase. Heliotrope is a green variety of chalcedony, containing red inclusions of iron oxide that resemble drops of blood, giving heliotrope its alternative name of bloodstone. In a similar variety, the spots are yellow instead, known as plasma. Moss agate
USS Heliotrope (1863) about 50 men up Mattox Creek. Three schooners and various types of supplies were captured or destroyed on this 2-day foray. The small gunboat continued her vital work of choking off Confederate supplies in the Potomac River area until mid-April, when she steamed for New York City, arriving 20 April. "Heliotrope" decommissioned 12 January 1865 and was sold 17 June to the Department of the Treasury for use with the Lighthouse Service. USS Heliotrope (1863) USS "Heliotrope" (1863) was a wooden steamer acquired by the Union Navy for use during the American Civil War. In addition to patrol duty, "Heliotrope"