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Opulent Opal

Short answer: Opal is hydrated amorphous silica. Precious opal shows play-of-color, flashes of spectral color that shift with the viewing angle, while common opal doesn't.

The effect comes from diffraction: precious opal is built from tiny silica spheres packed in a regular lattice, and their size and spacing set which colors appear. Australia produces most of the world's precious opal. Folklore around opals ranges from good luck to bad luck. The footage shows polished and rough opals, with the presenter.

VideoWrite-up1 sources
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What should you know about Opulent Opal?

Quick facts. Each one stands alone and has a stable ID you can cite.

  1. Opal is hydrated amorphous silica.

    DD-169-F01 · Write-up · Exhibit A (Amorphous silica)

  2. Precious opal shows play-of-color.

    DD-169-F02 · Write-up · Exhibit B (Play-of-color)

Video transcript: Opulent Opal: Opal's Colors Come From Tiny Stacked Spheres of Silica

Opal is a mesmerizing gemstone renowned for its play of color a phenomenon where it displays vibrant flashes of iridescence that change with the viewing angle. DID YOU KNOW? This captivating optical effect is created by the diffraction of light as it interacts with silica spheres within the stone. Opals come in a spectrum of colors and their beauty lies in the unique patterns and combinations of hues they exhibit. The play of color can include shades of orange, green, blue, and violet, making opals one of the most colorful Beyond their aesthetic appeal opals have been surrounded by myths and Some cultures believed opals brought good luck while others considered them symbols of hope. Regardless of superstitions opals remain highly prized in the world of for their unique and ever-changing beauty. NOW YOU KNOW!

Burned-in captions, read frame by frame (see transcript.md) · 43.2s Reel ·

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Opulent Opal: Opal's Colors Come From Tiny Stacked Spheres of Silica Instagram Reel · · 43.2s

The write-up

Opal's colors come from tiny stacked spheres of silica. The spheres diffract light like a grating.

  1. Exhibit A

    Amorphous silica

    Opal is hydrated amorphous silica.

  2. Exhibit B

    Play-of-color

    Precious opal shows play-of-color.

  3. Exhibit C

    Silica spheres

    Packed silica spheres diffract light.

  4. Exhibit D

    Sphere size

    Sphere size and spacing set the colors.

  5. Exhibit E

    Australia

    Australia produces most precious opal.

Questions people ask about Opulent Opal

What is opal made of?

It's amorphous.

Source: Write-up · Exhibit A (Amorphous silica) · Wikipedia: Opal

What is opal's color flash called?

It shifts with angle.

Source: Write-up · Exhibit B (Play-of-color) · Wikipedia: Opal

What causes it?

A natural grating.

Source: Write-up · Exhibit C (Silica spheres) · Wikipedia: Opal

What sets the colors?

Bigger spheres show reds.

Source: Write-up · Exhibit D (Sphere size) · Wikipedia: Opal

Which country produces most precious opal?

Most of the world's supply.

Source: Write-up · Exhibit E (Australia) · Wikipedia: Opal

Test Your Knowledge

All quizzes →

5 questions, all from this case file. Answers are revealed instantly.

  1. What is opal made of?

    1. Hydrated silica
    2. Carbon
    3. Corundum
    4. Salt
    Show the answer

    Answer: A. Hydrated silica It's amorphous. Source: Write-up · Exhibit A (Amorphous silica) · Wikipedia: Opal

  2. What is opal's color flash called?

    1. Play-of-color
    2. Fluorescence
    3. Rust
    4. Glare
    Show the answer

    Answer: A. Play-of-color It shifts with angle. Source: Write-up · Exhibit B (Play-of-color) · Wikipedia: Opal

  3. What causes it?

    1. Diffraction by silica spheres
    2. Paint
    3. Heat
    4. Magnetism
    Show the answer

    Answer: A. Diffraction by silica spheres A natural grating. Source: Write-up · Exhibit C (Silica spheres) · Wikipedia: Opal

  4. What sets the colors?

    1. Sphere size and spacing
    2. The moon
    3. Weight
    4. Age only
    Show the answer

    Answer: A. Sphere size and spacing Bigger spheres show reds. Source: Write-up · Exhibit D (Sphere size) · Wikipedia: Opal

  5. Which country produces most precious opal?

    1. Australia
    2. Iceland
    3. Canada
    4. Chile
    Show the answer

    Answer: A. Australia Most of the world's supply. Source: Write-up · Exhibit E (Australia) · Wikipedia: Opal

Cite this case file

Easterling, Marcus. "Opulent Opal." The Detail Department (DetailEnjoyer), case file DD-169, last updated Jan 8, 2024. https://detailenjoyer.com/case/opulent-opal/

Permalink: https://detailenjoyer.com/case/opulent-opal/ · Last updated

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