Definition

Noun: 1. A dark mineral: A naturally occurring, inorganic solid substance characterized by a dark color. It is a specific mineral composed primarily of oxides of yttrium, erbium, and tantalum, often containing other rare-earth elements.

Usage

• Fergusonite is a rare mineral primarily of interest to mineralogists, geologists, and collectors.
• It is typically identified and studied in a laboratory setting due to its complex composition and rarity.

Examples

• "The geologist identified the black, dense crystal as fergusonite after conducting an X-ray diffraction analysis."
• "This specimen of fergusonite is notable for its high tantalum content."
• "Fergusonite is one of several minerals that are important sources of rare-earth elements."

Advanced Usage

• The mineral is named after Robert Ferguson of Raith (1767–1840), a Scottish politician and mineral collector.
• In scientific contexts, its chemical formula is often given as (Y,Er,Ce,La,etc.)(Nb,Ta)O₄, indicating its variable composition.

Variants and Related Words

• Fergusonite-(Y): The most common variety, where yttrium (Y) is the dominant rare-earth element.
• Fergusonite-(Ce): A less common variety where cerium (Ce) is the dominant rare-earth element.

Synonyms

• Mineral (This is the general category; "fergusonite" is a specific type of mineral. There is no true single-word synonym for this specific mineral name.)

Antonyms

• There is no direct antonym for a specific mineral name. In a broad sense, one could contrast it with organic compound or synthetic material, as fergusonite is a natural, inorganic mineral.

Noun

1. a dark mineral consisting of oxides of yttrium and erbium and tantalum and other minerals