What does pleochroism mean?
Pleochroism refers to the property of certain crystals that display different colours when viewed from different directions. This phenomenon occurs due to the way the crystal's structure interacts with light. Pleochroism is a key characteristic used in mineralogy to identify and classify crystals. The term is derived from the Greek words 'pleo' meaning 'more' and 'chroma' meaning 'colour'. Pleochroism is often observed in minerals such as tanzanite, tourmaline, and andalusite. It is an important property that helps distinguish these minerals from others. The study of pleochroism has applications in geology, materials science, and gemology. Understanding pleochroism can provide insights into the composition and structure of crystals.
nounThe property of certain crystals of having different colours when viewed from different directions.
- The property of certain crystals of having different colours when viewed from different directions.
- A specific instance of pleochroism in a crystal or mineral.
"The mineral tanzanite exhibits a strong pleochroism, appearing blue in one direction and purple in another."
"The mineralogist studied the pleochroism of the tourmaline crystal."
"The gemstone's pleochroism made it highly prized by collectors."
The plural form is used to describe multiple instances of pleochroism.
"The geologist observed several pleochroisms in the crystal collection."
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of pleochroism
The term 'pleochroism' originates from the Greek words 'pleo' (πλέων) meaning 'more' and 'chroma' (χρῶμα) meaning 'colour'. The term was first used in the 19th century to describe the property of certain crystals that exhibit multiple colours. The study of pleochroism is closely related to the fields of mineralogy and crystallography.
Usage notes
Pleochroism is a technical term used primarily in mineralogy and crystallography. It has a neutral connotation and is often used to describe the optical properties of crystals.