DATABASE

Glass & tool reference

Twenty-four glasses with their expansion coefficients, annealing and strain points, working ranges, colours, origins and price bands. Sort any column, filter by family, and compare up to three side by side.

Family

Annealing point

Colour

Origin

Price band

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Compare
	Soda-lime (furnace glass)	Soda-lime	90	510 °C	470 °C	1000 – 1150 °C	Clear / any	USA, Germany, China	Low
Worked by Furnace, off-hand Annealing point 510 °C — stress relaxes in minutes here Strain point 470 °C — below this, stress effectively never relaxes Working range 1000 – 1150 °C Coefficient of expansion 90 × 10⁻⁷/°C Origin USA, Germany, China Price band Low Mixing this glass with another is only safe if the two coefficients are within about 5 %. Check a pair in the COE calculator.
	Soda-lime (soft, 96 COE)	Soda-lime	96	505 °C	465 °C	980 – 1140 °C	Clear / any	USA, China	Low
Worked by Fusing, slumping Annealing point 505 °C — stress relaxes in minutes here Strain point 465 °C — below this, stress effectively never relaxes Working range 980 – 1140 °C Coefficient of expansion 96 × 10⁻⁷/°C Origin USA, China Price band Low Mixing this glass with another is only safe if the two coefficients are within about 5 %. Check a pair in the COE calculator.
	Soda-lime (bottle glass)	Soda-lime	88	515 °C	475 °C	1000 – 1150 °C	Green / amber	Recycled	Free – low
Worked by Recycled furnace work Annealing point 515 °C — stress relaxes in minutes here Strain point 475 °C — below this, stress effectively never relaxes Working range 1000 – 1150 °C Coefficient of expansion 88 × 10⁻⁷/°C Origin Recycled Price band Free – low Mixing this glass with another is only safe if the two coefficients are within about 5 %. Check a pair in the COE calculator.
	Borosilicate (33 COE)	Borosilicate	33	565 °C	510 °C	1150 – 1250 °C	Clear / any	USA, Germany, China	Medium
Worked by Lampwork, furnace, scientific Annealing point 565 °C — stress relaxes in minutes here Strain point 510 °C — below this, stress effectively never relaxes Working range 1150 – 1250 °C Coefficient of expansion 33 × 10⁻⁷/°C Origin USA, Germany, China Price band Medium Mixing this glass with another is only safe if the two coefficients are within about 5 %. Check a pair in the COE calculator.
	Borosilicate (hard, 29 COE)	Borosilicate	29	570 °C	515 °C	1180 – 1280 °C	Clear	Germany, USA	High
Worked by Scientific, high-temperature Annealing point 570 °C — stress relaxes in minutes here Strain point 515 °C — below this, stress effectively never relaxes Working range 1180 – 1280 °C Coefficient of expansion 29 × 10⁻⁷/°C Origin Germany, USA Price band High Mixing this glass with another is only safe if the two coefficients are within about 5 %. Check a pair in the COE calculator.
	Lead crystal (full lead)	Lead crystal	92	440 °C	400 °C	950 – 1050 °C	Clear, high brilliance	UK, Czechia, Ireland	High
Worked by Cut crystal, stemware Annealing point 440 °C — stress relaxes in minutes here Strain point 400 °C — below this, stress effectively never relaxes Working range 950 – 1050 °C Coefficient of expansion 92 × 10⁻⁷/°C Origin UK, Czechia, Ireland Price band High Mixing this glass with another is only safe if the two coefficients are within about 5 %. Check a pair in the COE calculator.
	Lead crystal (half lead)	Lead crystal	90	455 °C	415 °C	960 – 1070 °C	Clear / tinted	China, Czechia	Medium
Worked by Tableware Annealing point 455 °C — stress relaxes in minutes here Strain point 415 °C — below this, stress effectively never relaxes Working range 960 – 1070 °C Coefficient of expansion 90 × 10⁻⁷/°C Origin China, Czechia Price band Medium Mixing this glass with another is only safe if the two coefficients are within about 5 %. Check a pair in the COE calculator.
	Lead-free crystal	Lead crystal	88	470 °C	430 °C	980 – 1080 °C	Clear, bright	Germany, China	Medium
Worked by Tableware, cut work Annealing point 470 °C — stress relaxes in minutes here Strain point 430 °C — below this, stress effectively never relaxes Working range 980 – 1080 °C Coefficient of expansion 88 × 10⁻⁷/°C Origin Germany, China Price band Medium Mixing this glass with another is only safe if the two coefficients are within about 5 %. Check a pair in the COE calculator.
	Fused quartz	Quartz	5.5	1120 °C	1070 °C	1700 – 2000 °C	Clear, UV-transparent	USA, Germany, Japan	Very high
Worked by Lampwork, scientific Annealing point 1120 °C — stress relaxes in minutes here Strain point 1070 °C — below this, stress effectively never relaxes Working range 1700 – 2000 °C Coefficient of expansion 5.5 × 10⁻⁷/°C Origin USA, Germany, Japan Price band Very high Mixing this glass with another is only safe if the two coefficients are within about 5 %. Check a pair in the COE calculator.
	Fused silica (optical)	Quartz	5.5	1140 °C	1080 °C	1800 – 2100 °C	Water clear	USA, Japan	Very high
Worked by Optical, laboratory Annealing point 1140 °C — stress relaxes in minutes here Strain point 1080 °C — below this, stress effectively never relaxes Working range 1800 – 2100 °C Coefficient of expansion 5.5 × 10⁻⁷/°C Origin USA, Japan Price band Very high Mixing this glass with another is only safe if the two coefficients are within about 5 %. Check a pair in the COE calculator.
	Aluminosilicate	Aluminosilicate	45	715 °C	660 °C	1200 – 1300 °C	Clear / amber	USA, Germany	High
Worked by Lampwork, high-temperature Annealing point 715 °C — stress relaxes in minutes here Strain point 660 °C — below this, stress effectively never relaxes Working range 1200 – 1300 °C Coefficient of expansion 45 × 10⁻⁷/°C Origin USA, Germany Price band High Mixing this glass with another is only safe if the two coefficients are within about 5 %. Check a pair in the COE calculator.
	Borosilicate (opal)	Borosilicate	33	560 °C	505 °C	1130 – 1230 °C	Opaque white	USA, Germany	Medium
Worked by Lampwork, sculpture Annealing point 560 °C — stress relaxes in minutes here Strain point 505 °C — below this, stress effectively never relaxes Working range 1130 – 1230 °C Coefficient of expansion 33 × 10⁻⁷/°C Origin USA, Germany Price band Medium Mixing this glass with another is only safe if the two coefficients are within about 5 %. Check a pair in the COE calculator.
	Soda-lime (opal)	Soda-lime	92	505 °C	465 °C	990 – 1130 °C	Opaque white	Italy, China	Medium
Worked by Furnace, blown opaque Annealing point 505 °C — stress relaxes in minutes here Strain point 465 °C — below this, stress effectively never relaxes Working range 990 – 1130 °C Coefficient of expansion 92 × 10⁻⁷/°C Origin Italy, China Price band Medium Mixing this glass with another is only safe if the two coefficients are within about 5 %. Check a pair in the COE calculator.
	Soda-lime (crystal clear)	Soda-lime	90	512 °C	472 °C	1000 – 1150 °C	Colourless, bright	Italy, Germany	Medium
Worked by Furnace, tableware Annealing point 512 °C — stress relaxes in minutes here Strain point 472 °C — below this, stress effectively never relaxes Working range 1000 – 1150 °C Coefficient of expansion 90 × 10⁻⁷/°C Origin Italy, Germany Price band Medium Mixing this glass with another is only safe if the two coefficients are within about 5 %. Check a pair in the COE calculator.
	Borosilicate (amber)	Borosilicate	33	562 °C	507 °C	1140 – 1240 °C	Amber	USA, China	Medium
Worked by Lampwork, apparatus Annealing point 562 °C — stress relaxes in minutes here Strain point 507 °C — below this, stress effectively never relaxes Working range 1140 – 1240 °C Coefficient of expansion 33 × 10⁻⁷/°C Origin USA, China Price band Medium Mixing this glass with another is only safe if the two coefficients are within about 5 %. Check a pair in the COE calculator.
	Borosilicate (cobalt blue)	Borosilicate	33	563 °C	508 °C	1140 – 1240 °C	Deep blue	USA, Germany	Medium
Worked by Lampwork, colour work Annealing point 563 °C — stress relaxes in minutes here Strain point 508 °C — below this, stress effectively never relaxes Working range 1140 – 1240 °C Coefficient of expansion 33 × 10⁻⁷/°C Origin USA, Germany Price band Medium Mixing this glass with another is only safe if the two coefficients are within about 5 %. Check a pair in the COE calculator.
	Soda-lime (cobalt blue)	Soda-lime	92	508 °C	468 °C	990 – 1140 °C	Deep blue	Italy, China	Low
Worked by Furnace, blown colour Annealing point 508 °C — stress relaxes in minutes here Strain point 468 °C — below this, stress effectively never relaxes Working range 990 – 1140 °C Coefficient of expansion 92 × 10⁻⁷/°C Origin Italy, China Price band Low Mixing this glass with another is only safe if the two coefficients are within about 5 %. Check a pair in the COE calculator.
	Soda-lime (ruby / gold)	Soda-lime	90	505 °C	465 °C	980 – 1120 °C	Ruby red	Italy, Germany	Very high
Worked by Furnace, gold-bearing Annealing point 505 °C — stress relaxes in minutes here Strain point 465 °C — below this, stress effectively never relaxes Working range 980 – 1120 °C Coefficient of expansion 90 × 10⁻⁷/°C Origin Italy, Germany Price band Very high Mixing this glass with another is only safe if the two coefficients are within about 5 %. Check a pair in the COE calculator.
	Soda-lime (copper ruby)	Soda-lime	91	503 °C	463 °C	980 – 1120 °C	Red, striking	Germany, USA	High
Worked by Furnace, striking colour Annealing point 503 °C — stress relaxes in minutes here Strain point 463 °C — below this, stress effectively never relaxes Working range 980 – 1120 °C Coefficient of expansion 91 × 10⁻⁷/°C Origin Germany, USA Price band High Mixing this glass with another is only safe if the two coefficients are within about 5 %. Check a pair in the COE calculator.
	Borosilicate (uranium)	Borosilicate	33	560 °C	505 °C	1140 – 1240 °C	Fluorescent yellow-green	Germany, USA	High
Worked by Lampwork, decorative Annealing point 560 °C — stress relaxes in minutes here Strain point 505 °C — below this, stress effectively never relaxes Working range 1140 – 1240 °C Coefficient of expansion 33 × 10⁻⁷/°C Origin Germany, USA Price band High Mixing this glass with another is only safe if the two coefficients are within about 5 %. Check a pair in the COE calculator.
	Phosphate glass	Phosphate	130	420 °C	380 °C	900 – 1000 °C	Clear / amber	USA	High
Worked by Specialist, sealing Annealing point 420 °C — stress relaxes in minutes here Strain point 380 °C — below this, stress effectively never relaxes Working range 900 – 1000 °C Coefficient of expansion 130 × 10⁻⁷/°C Origin USA Price band High Mixing this glass with another is only safe if the two coefficients are within about 5 %. Check a pair in the COE calculator.
	Fluorite opal	Opal	95	480 °C	440 °C	950 – 1080 °C	Translucent white	Italy, Czechia	Medium
Worked by Furnace, opaline Annealing point 480 °C — stress relaxes in minutes here Strain point 440 °C — below this, stress effectively never relaxes Working range 950 – 1080 °C Coefficient of expansion 95 × 10⁻⁷/°C Origin Italy, Czechia Price band Medium Mixing this glass with another is only safe if the two coefficients are within about 5 %. Check a pair in the COE calculator.
	Recycled bottle cullet	Soda-lime	88	515 °C	475 °C	1000 – 1150 °C	Green / amber	Local	Free
Worked by Furnace, recycled Annealing point 515 °C — stress relaxes in minutes here Strain point 475 °C — below this, stress effectively never relaxes Working range 1000 – 1150 °C Coefficient of expansion 88 × 10⁻⁷/°C Origin Local Price band Free Mixing this glass with another is only safe if the two coefficients are within about 5 %. Check a pair in the COE calculator.
	Flat glass cullet	Soda-lime	89	513 °C	473 °C	1000 – 1150 °C	Pale green	Local	Free
Worked by Furnace, recycled Annealing point 513 °C — stress relaxes in minutes here Strain point 473 °C — below this, stress effectively never relaxes Working range 1000 – 1150 °C Coefficient of expansion 89 × 10⁻⁷/°C Origin Local Price band Free Mixing this glass with another is only safe if the two coefficients are within about 5 %. Check a pair in the COE calculator.

Reading the table

The two numbers that decide most failures are the coefficient of expansion and the annealing point, and they are the two the table is sorted around.

Coefficient of expansion

How much the glass grows per degree. Two glasses joined together must be within about 5 % of each other, and no annealing schedule will rescue a pair that is not. Check a pair.

Annealing and strain points

Soak at the annealing point, and do not re-enter the strain point on the way down. The gap between them is the annealing range. Build a schedule.

Working range

The span where the glass can be gathered, blown and shaped. Below it the glass breaks; above it, it runs off the pipe. Try it in the simulator.