black opal
Học thuậtThân thiện
Definition
Noun: * A dark-colored variety of the mineral opal, characterized by a dark body tone (often black, dark blue, or dark green) which provides a striking contrast to vibrant internal flashes of color, typically green or red.
Usage
"Black opal" is a specific gemological term. It is used as a countable noun to refer to individual gems or as an uncountable noun to refer to the material in general. Its primary use is in the contexts of jewelry, gem collecting, and mineralogy.
Examples
- The jeweler showed her a magnificent black opal set in a ring.
- Black opal is among the rarest and most valuable types of opal.
- This pendant features a black opal from Lightning Ridge, Australia.
Advanced Usage
- The term is often used in comparisons to highlight rarity and value: "While white opal is beautiful, a fine black opal with a red flash is considered the pinnacle."
- In descriptive writing, it can be used metaphorically to describe something with a dark base and colorful, shifting details: "The night sky was a black opal, dotted with shimmering stars."
Variants and Related Words
- Opal (n): The broader category of hydrated silica gemstones known for their "play-of-color."
- White opal (n): An opal with a light or white body color.
- Boulder opal (n): Opal that forms within ironstone matrix.
- Fire opal (n): An opal known for its orange, red, or yellow body color, which may or may not show play-of-color.
- Play-of-color (n): The optical phenomenon causing the spectral colors seen in opals.
Synonyms
- Dark opal
- Precious opal (when specifying the play-of-color variety, though "precious opal" includes other body tones)
Antonyms
- White opal
- Light opal
Related Phrases
- Harlequin opal: A pattern within black or other opals where the color flashes are arranged in a broad, mosaic-like pattern.
- Pinfire opal: A pattern where the color flashes are small and pinpoint-like.
Noun
- a dark colored opal with internal reflections of green or red