Opal: The Shifting Spectrum Between Sapphire and Topaz

The gemstone opal, a hydrated silica mineral, is consistently identified as the birthstone positioned between sapphire and topaz in various crossword puzzles and gemological references. While the provided sources primarily focus on its recognition as a crossword puzzle answer, they collectively establish opal’s place within the broader context of birthstones and gemstones. This article will explore the available information regarding opal, drawing exclusively from the provided sources, and detailing its identification, historical appearances in puzzles, and associated characteristics.

Historical Recognition in Crossword Puzzles

The primary context of the provided sources centers around the identification of opal as the solution to the crossword puzzle clue “Birthstone between sapphire and topaz.” Multiple sources – including answers.org, tryhardguides.com, danword.com, crosswordheaven.com, crossword-solver.com, wordfinder.yourdictionary.com, and crossword-solver.io – confirm “opal” as the four-letter answer. These sources indicate the clue has appeared in various crossword publications, including the LA Times (June 14, 2024, and earlier instances in 2016 and 2007), USA Today (December 10, 2018), the New York Sun (November 19, 2007), and the Washington Post (July 18, 2006). The Daily Pop Crossword (June 22, 2025) is also noted as featuring this clue. This repeated appearance highlights opal’s recognition as a gemstone fitting this specific positional description within the traditional birthstone order.

Gemological Characteristics

The sources define opal as a “translucent mineral consisting of hydrated silica of variable color.” It is further described as a gemstone that can exhibit “color flashes” and a “milky-white” appearance. Additional descriptors include “hydrophane” and “isopyre,” suggesting variations within the opal family. The sources also categorize opal as a “gem” alongside sapphire, indicating its value as a gemstone. One source notes it as a shade of blue, and another references “hyalite” as a type of opal.

Associated Terminology and Clues

Several related terms and clues appear alongside the primary identification of opal. These include references to “October gem,” suggesting a connection to the October birthstone. The term “fire opal” is also mentioned, indicating a specific variety of opal known for its vibrant color. The sources also link opal to the concept of “shade of blue” and “opal glass,” potentially referencing both the stone’s color and imitations. The clue “memorable 1995 hurricane” is listed as a related clue, though its connection to opal is not explained within the provided materials.

Historical Puzzle Appearances

The sources demonstrate a history of opal appearing in crossword puzzles spanning several decades. The earliest documented instance is from 2006 in the Washington Post, with subsequent appearances in 2007, 2016, 2018, and 2024. This consistent inclusion suggests a sustained recognition of opal within popular culture and a familiarity with its status as a gemstone. The LA Times appears to be a frequent publisher of this clue, with multiple instances recorded across different puzzle formats (Daily, Mini).

Summary of Properties

The following table summarizes the gemological properties and associated terms mentioned in the provided sources:

Property/Term	Description
Mineral Composition	Hydrated Silica
Transparency	Translucent
Color	Variable, including milky-white and shades of blue
Phenomena	Color flashes
Varieties	Fire Opal, Hyalite, Isopyre, Hydrophane
Association	October Gem
Related Terms	Opal Glass

Limitations of the Sources

It is crucial to acknowledge the limited scope of the provided sources. They are overwhelmingly focused on the gemstone’s role as a crossword puzzle answer and offer minimal detail regarding its geological formation, mining locations, historical lore, or metaphysical properties. The sources do not provide information on opal’s hardness, refractive index, chemical formula, or detailed grading criteria. The connection between “opal” and the clue “memorable 1995 hurricane” remains unexplained. The sources are primarily concerned with solving a puzzle, not providing a comprehensive gemological overview.

Conclusion

The provided sources consistently identify opal as the birthstone positioned between sapphire and topaz, primarily within the context of crossword puzzle clues. While the information is limited, it establishes opal as a recognized gemstone with a history of appearing in popular culture. The sources describe opal as a translucent, hydrated silica mineral exhibiting variable color and notable phenomena like color flashes. Further research, utilizing more comprehensive gemological resources, would be necessary to provide a complete understanding of opal’s properties, history, and significance.