Pleonaste
Embed This Widget
Add the script tag and a data attribute to embed this widget.
Embed via iframe for maximum compatibility.
<iframe src="https://gemfyi.com/iframe/entity/pleonaste/" width="420" height="400" frameborder="0" style="border:0;border-radius:10px;max-width:100%" loading="lazy"></iframe>Paste this URL in WordPress, Medium, or any oEmbed-compatible platform.
https://gemfyi.com/entity/pleonaste/Add a dynamic SVG badge to your README or docs.
[](https://gemfyi.com/entity/pleonaste/)Use the native HTML custom element.
Add one script tag to your page:
<div data-gemfyi="entity" data-slug="pleonaste"></div>
<script src="https://cdn.jsdelivr.net/npm/gemfyi-embed@1/dist/embed.min.js" defer></script>
Embed as an iframe:
<iframe src="https://gemfyi.com/iframe/entity/pleonaste/?style=modern&theme=light" width="420" height="400" frameborder="0" loading="lazy" style="border:0;border-radius:10px;max-width:100%"></iframe>
Paste the URL in WordPress, Medium, or Ghost:
https://gemfyi.com/ja/gems/pleonaste/
Shields.io-compatible SVG badge:
Web Component:
<gemfyi-entity slug="pleonaste"></gemfyi-entity>
<script src="https://cdn.jsdelivr.net/npm/gemfyi-embed@1/dist/embed.min.js" defer></script>
Physical & Optical Properties
Category
Semi-Precious Gems
Mohs Hardness
8.0
Specific Gravity
3.8
Refractive Index
1.78
Crystal System
Isometric
Luster
Vitreous
Cleavage
None
Color
various
Mohs Hardness
| Mohs | Reference mineral | Pleonaste |
|---|---|---|
| 1 | Talc | |
| 2 | Gypsum | |
| 3 | Calcite | |
| 4 | Fluorite | |
| 5 | Apatite | |
| 6 | Orthoclase | |
| 7 | Quartz | |
| 8 | Topaz | ● |
| 9 | Corundum | |
| 10 | Diamond |
Crystal System
Value & Market
Price Tier
Fine ($500-5,000/ct)
Where to Buy Pleonaste
Blue Nile
Fine jewelry retailer
James Allen
Gemstone jewelry
Brilliant Earth
Ethically sourced gems
Amazon
Wide selection
Links may earn a commission at no extra cost to you.
About Pleonaste
プレオナスト（鉄スピネル）は、鉄に富む濃黒色〜暗黒緑色のスピネル変種で、ガラス光沢〜亜金属光沢を持ちます。変成岩・火成岩に副次鉱物として産し、スリランカ・マダガスカル・ヨーロッパ各地に産地があります。宝石として利用されることは稀ですが、その深い黒色と等軸晶系の結晶形が独特のコレクター標本として評価されています。
On this page
Jewelry Use
Durability
9/10
Suitable for daily wear
Science FYI Family
Frequently Asked Questions
What is Pleonaste?
プレオナスト（鉄スピネル）は、鉄に富む濃黒色〜暗黒緑色のスピネル変種で、ガラス光沢〜亜金属光沢を持ちます。変成岩・火成岩に副次鉱物として産し、スリランカ・マダガスカル・ヨーロッパ各地に産地があります。宝石として利用されることは稀ですが、その深い黒色と等軸晶系の結晶形が独特のコレクター標本として評価されています。
What is the hardness of Pleonaste?
Pleonaste has a Mohs hardness of 8.0, making it excellent for use in jewelry.
What color is Pleonaste?
Pleonaste is primarily Various.
How much does Pleonaste cost?
Pleonaste falls into the Fine ($500-5,000/ct) price range. Prices vary based on color, clarity, cut, and origin.
What is the crystal system of Pleonaste?
Pleonaste belongs to the Isometric crystal system.