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Octagon Buff Top Single Bevel Genuine Black Onyx

Part # 947-F11 Only 1 left Weight -- lb -- g
Current price $3.00
Volume pricing
Total qty Discount Per unit You save
1 – 2 $3.00
3 – 4 5% off $2.85 $0.15
5 – 9 10% off $2.70 $0.30
10 + 12% off $2.64 $0.36
Add 2 more for 5% off, saves another $0.15 each.
Select Size: 9x7mm

Black onyx, also known as black agate, is dyed black chalcedony — one of the most enduring and versatile gem materials in the jeweler's palette. Chalcedony is composed of microscopic quartz crystals invisible to the naked eye. Natural black chalcedony is exceptionally rare; as a result, all black chalcedony on the market is grey chalcedony that has been chemically treated to achieve its signature deep, uniform black color. Black onyx remains the top-selling chalcedony in the trade and carries a rich history in jewelry design, most notably as a staple of the Art Deco movement.

These octagon buff top cabochons feature a single bevel cut and a polished, opaque black surface that photographs beautifully and pairs well with both white and yellow metals. Ideal for rings, pendants, brooches, and earrings across a range of jewelry styles.

Clean with warm, soapy water. Use of ultrasonic and steam cleaners is generally considered safe for this material.

Features

  • Genuine black onyx (dyed black chalcedony)
  • Octagon buff top with single bevel profile
  • Uniform opaque black color throughout
  • Smooth, polished cabochon surface
  • Treatment: Dyed — industry-standard process for all black chalcedony
  • Historically significant gem material associated with Art Deco jewelry design
  • Safe for ultrasonic and steam cleaning

Specifications

Stone Type Black Onyx (Dyed Black Chalcedony)
Cut Style Octagon Buff Top, Single Bevel
Color Uniform Opaque Black
Treatment Dyed
Transparency Opaque
Cleaning Warm soapy water; ultrasonic and steam generally safe

Available Options

Part # Size
947-F11 9x7mm
947-F12 12x10mm
947-F13 14x12mm
947-F14 16x12mm
California Prop 65 Warning California Prop 65 Warning:
Cancer and Reproductive Harm. www.P65warnings.ca.gov.
Brand
Otto Frei
Part #
947-F11
Type
Cabochon
Dimensions
0.1 in x 0.1 in x 0.1 in
Stone Type
Black Onyx (Dyed Black Chalcedony)
Cut Style
Octagon Buff Top, Single Bevel
Color
Uniform Opaque Black
Treatment
Dyed
Transparency
Opaque
Cleaning
Warm soapy water; ultrasonic and steam generally safe