3.1" Goethite Pseudomorphs after Gypsum - Chihuahua, Mexico

This is a classic pseudomorph specimen out of the Santa Eulalia Mining District of Chihuahua, Mexico. It's a formation of botryoidal goethite pseudomorphed after gypsum, with some secondary gypsum crystals along one edge. This occurrence required the gypsum to first crystallize, be overgrown with goethite, and later dissolve, leaving behind a hollow cast. The specimen measures 3.1" wide and is accompanied by an acrylic display stand.

About Goethite

Goethite is an iron-bearing hydroxide mineral composed primarily of iron(III) oxide-hydroxide (FeO(OH)). It commonly forms as a weathering product of iron-rich minerals and is one of the primary components of rust and limonite. Goethite often develops in botryoidal, stalactitic, or massive forms, though it can also occur as acicular or needle-like crystals. Its color ranges from yellow-brown to reddish-brown or black, with a dull to submetallic luster. This mineral is widespread in soil and sedimentary environments and frequently associated with hematite, magnetite, and quartz. Named after the German poet and philosopher Johann Wolfgang von Goethe, goethite has been used historically as a pigment and remains a significant iron ore in some regions.
FOR SALE
$35
DETAILS
SPECIES
Goethite
LOCATION
Santa Eulalia Mining District, Chihuahua, Mexico
SIZE
Entire specimen 3.1 x 2.7"
CATEGORY
ITEM
#330399