Glasslinks Heart and Circle

The Glasslinks Heart and Circle mold from Colour de Verre casts two shapes in a single firing: an open heart and a circle. Both pieces are sized to link into the Colour de Verre Oval and Diamond Glasslinks chains, making this a focused tool for glass jewelry work. The mold footprint is 5.5 inches by 2.875 inches, and each cavity takes a modest amount of fine or powdered frit, with 7 grams going into the heart and 8 grams into the circle.

As a reusable ceramic casting mold it is COE agnostic, so COE96, COE90, or other fusible glass all work in the same cavities. Colour de Verre recommends a cooler firing range of 1335 to 1350 F (725 to 730 C) with a hold of 25 to 30 minutes before annealing, which suits the fine detail of these small shapes. Prime the mold before every firing with ZYP BN Lubricoat or Hotline Primo Primer.

What does the Glasslinks Heart and Circle mold make?
It casts one open heart and one circle per firing, both sized to link into Colour de Verre Oval and Diamond Glasslinks chains. They can also serve as small stand-alone focal pieces for jewelry.

How much glass do I need per cavity?
Colour de Verre lists 7 grams of fine or powdered frit for the heart cavity and 8 grams for the circle cavity.

What COE glass can I use?
Any COE. Ceramic casting molds are COE agnostic, so the same mold works with COE96, COE90, or other fusible glass. Match your firing schedule to the glass you are using.

How do I prep this mold before firing?
Colour de Verre molds must be primed before every firing. Apply ZYP BN Lubricoat or Hotline Primo Primer to the cavities and let the coating dry completely before adding frit.

Specifications

• SKU: 181665
• Manufacturer: Colour de Verre
• Makes: 1 open heart and 1 circle per firing
• Designed for: Colour de Verre Oval and Diamond Glasslinks chains
• Mold size: 5.5 inches L x 2.875 inches W (14 x 7.3 cm)
• Fill weight: 7 grams (heart cavity), 8 grams (circle cavity)
• Firing temp: 1335 to 1350 F (725 to 730 C), hold 25 to 30 minutes
• Material: ceramic kiln casting mold, reusable
• Glass: any COE (COE agnostic)

Working Notes

These are guidelines, not guarantees. Every kiln fires a little differently, so test a small run first when the result matters and follow the Colour de Verre project sheet for this mold.

• Prime both cavities before every firing with ZYP Boron Nitride Mold Primer or Hotline Primo Primer, and let the coating dry fully before adding frit.
• Fill the heart cavity with 7 grams of fine or powdered frit and the circle cavity with 8 grams. Weigh the frit for consistent results.
• The mold is COE agnostic. Match your firing schedule and anneal soak to the glass you are using.
• Colour de Verre recommends heating no faster than about 350 F (195 C) per hour. Fire to between 1335 and 1350 F (725 to 730 C) and hold for 25 to 30 minutes. Do not exceed about 1450 F (785 C). Then cool to an anneal soak suited to your glass: about 950 F for COE96 or about 900 F for COE90.
• Let the kiln cool fully before removing the cast pieces. Re-prime the cavities before each subsequent firing.

Colour de Verre Suggested Firing Schedule

This is a suggested starting point, not a guarantee. Every kiln fires differently. Follow the Colour de Verre project sheet for this mold and test a small run first.

• Ramp rate: no faster than about 350 F (195 C) per hour
• Target temperature: 1335 to 1350 F (725 to 730 C)
• Hold: 25 to 30 minutes
• Maximum temperature: no more than about 1450 F (785 C)
• Anneal soak: about 950 F for COE96, about 900 F for COE90

Helpful downloads: Priming Molds With ZYP Spray (PDF)

Description updated: July 6, 2026

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