Lansfordite is a mineral that belongs to the hydrous magnesium carbonate group, characterized by its chemical composition of magnesium carbonate pentahydrate (MgCO3·5H2O). It is named after the locality of Lansford, Pennsylvania, where it was first discovered.
Lansfordite typically forms as a secondary mineral in evaporative environments, commonly appearing as white to colorless, fibrous, or radiating masses. Its crystal system is monoclinic, and it exhibits a prismatic or needle-like crystal habit. The mineral has a Mohs hardness of 2 to 2.5, making it relatively soft and easily scratchable.
In terms of its physical properties, lansfordite is transparent to translucent with a vitreous luster. It has a low specific gravity ranging from 1.86 to 1.9, indicating its lightweight nature. The mineral typically effervesces when it comes into contact with acids due to the presence of carbonate ions in its structure.
Lansfordite has limited applications, mainly as a scientific specimen and as a potential source of magnesium. It can be found in various evaporitic environments, including salt flats, caves, and dry lakebeds. Notable occurrences of lansfordite can be found in the United States, Argentina, Mexico, Germany, and Antarctica.
As a relatively uncommon mineral, lansfordite is of interest to mineralogists and collectors who appreciate its unique crystal structure and associations with other mineral species. Its study also contributes to a better understanding of the formation and properties of hydrous magnesium carbonates in geological environments.
