Short answer: Colored borosilicate comes from a handful of specialist makers, but the thing that actually decides how a rod behaves in your flame is the colorant chemistry inside it, not the logo on the box. Silver-bearing colors strike and haze, cadmium colors punish overheating, cobalt blues shrug off almost anything, and that holds true whoever melted the rod. Northstar Glassworks (Borocolour) is the documentation-heavy standard bearer and now also produces the TAG (Trautman Art Glass) line; Glass Alchemy teaches a neutral-flame default and explains striking through crystal growth; Momka’s Glass has been melting bright color since 2004; Parramore Colors and Molten Aura Labs serve distinctive niches; small-batch makers like Boro Batch run limited colors; and Chinese producers such as Lunar Glass and Tianyuan supply import color at lower prices. All of it is COE 33 borosilicate. The differences are chemistry, consistency, documentation, and format, and the maker’s own per-color notes always beat any general rule.
If flame chemistry itself is new to you, read neutral, oxidizing, and reducing flames explained first. This article assumes you can set and recognize all three.
Colorants decide behavior; brands decide consistency and support
It’s tempting to sort working advice by brand, but that gets the causation backwards. A color works the way it works because of what’s in it and what effect it’s designed to produce:
- Silver-saturated colors shift, strike, mirror, and haze with flame chemistry and heat history, whoever makes them.
- Cadmium-based brights (yellows, oranges, reds, the crayon-style opaques) are dense, opaque, and intolerant of overheating.
- Stable workhorse colorants (cobalt blues, chrome greens, most basic transparents) tolerate sloppy chemistry while your hands learn.
What the brand actually tells you is how consistent the melt is batch to batch, how good the documentation is, what formats you can buy, and how the maker names and organizes its chemistry. That’s why every serious color house publishes per-color working notes. Northstar’s quick guide and Glass Alchemy’s blog series are the canonical examples, and “how do I work this color?” is always answered per color, per maker, not per hue.
One definition before the brand tour: silver glass is colored boro whose look comes from silver in the melt. Colors that shift, haze, mirror, or develop metallic luster depending on flame chemistry and heat history. Every major maker sells silver-bearing colors; the behavior is covered in striking and silver glass basics.
Northstar Glassworks: Borocolour, plus the TAG line
Northstar Glassworks makes the Borocolour line, one of the longest-established colored-boro palettes and often the first brand a new boro worker buys. Two things define the Northstar experience for a buyer:
- Documentation. Northstar’s quick guide gives per-color working notes across the line, and its flame settings page is one of the clearest manufacturer statements on flame chemistry anywhere.
- The oxidizing-first default. Northstar’s guidance is that most of its colors should be worked in a neutral-to-oxidizing flame, because unwanted reduction damages much of the palette, muddying transparents and hazing surfaces. Reduction is treated as a deliberate, separate technique for the colors designed for it, which get their own reduction page.
Northstar also sells silver-saturated striking colors alongside its stable opaques and transparents, so a single Northstar order can span the easiest and hardest-to-work glass you own.
TAG (Trautman Art Glass): the silver-strike name, now made by Northstar
Trautman Art Glass is the brand most identified with striking and silver-saturated boro: colors that develop through heat cycles and flame chemistry rather than coming out of the flame finished. The TAG name traces back to Paul Trautman, a foundational figure in colored boro who was behind Northstar’s original color operation in the 1980s before later founding TAG as its own factory.
The corporate picture has since come full circle: TAG colors are now produced and sold under Northstar Glassworks. Northstar’s store carries a dedicated TAG Rods line and says it has been reworking TAG colors for air content and color consistency. For buyers this mostly means TAG classics (Slyme and the silver-strike families) are ordered from the same place as Borocolour, and old third-party listings of TAG stock may be aging inventory. If striking colors are what draws you to TAG, read striking and silver glass basics before your first rod, because these are the least beginner-proof colors in boro.
Glass Alchemy: numbered chemistry, neutral flames, and Crayons
Portland’s Glass Alchemy approaches color like a chemistry company. Its catalog runs on a numbering system, explained in its own blog post, that encodes color family and formulation, so related colors group together by number rather than by fanciful name alone.
Its flame guidance starts from a different default than Northstar’s: Glass Alchemy’s tutorial on setting a neutral flame teaches the neutral flame as the baseline for working its color, and the company explains striking behavior in terms of crystal growth: the size of the colorant crystals that form as the glass cycles through heat determines the color you end up with, which is why timing and temperature matter as much as flame chemistry.
Glass Alchemy is also known for its Crayon line: dense, opaque, cadmium-based brights. Two buyer’s notes there. First, the Crayons were discontinued at one point and later brought back, so check current availability rather than assuming any specific color is in stock. Second, cadmium colors (like silver colors) reward good ventilation and punish overheating. Keep fumes out of your breathing zone, and see boro color troubleshooting for what boiling and burning a color looks like.
Momka’s Glass: the bright-color OG
Momka’s Glass (momkasglass.com) has been melting colored boro in Seattle since 2004, founded by Momka Peeva, a Bulgarian-born chemical engineer who specialized in glass technology before coming to the United States. Her claim to history: at a time when colored boro skewed dark and muted, she developed some of the first genuinely bright, crayon-vivid boro colors, and the line made her name among flameworkers (KNKX profile). Today Momka’s produces dozens of transparent and opaque COE 33 colors across the spectrum. If you want saturated brights with a long track record behind them, this is one of the original sources.
Parramore Colors: a veteran’s distinctive palette
Parramore Colors (rogerparramore.com), formerly The New Color Company, is the color line associated with veteran lampworker Roger Parramore. The palette leans toward distinctive, often muted and classical tones (denims, golds, taupes, soft blues) rather than chasing the silver-strike arms race, and the line’s stated hallmark is consistency, sold as first-quality rod. It’s a strong pick for sculptural and vessel workers who want reliable, coordinated color rather than reactive drama.
Molten Aura Labs: sandcrafted color in three tone families
Molten Aura Labs is a newer maker whose pitch is what it calls “sandcrafted” glass, its term for melting color from raw materials rather than remelting other makers’ glass. That is Molten Aura’s own characterization of its process and its competitors’ (source). The company organizes its palette into three tone families, giving the line a designed, coordinated feel. One terminology note: Molten Aura writes its expansion spec as 33CTE, the same COE 33 borosilicate family as everyone else here, just written in the coefficient-of-thermal-expansion style.
Boro Batch and other small-batch makers
Beyond the established houses, small independent makers like Boro Batch (borobatch.com) melt limited-run specialty colors. The appeal is distinctive colors you can’t get elsewhere; the trade-offs are availability (runs sell out and may not repeat) and thinner documentation than Northstar’s or Glass Alchemy’s. Treat small-batch colors as “buy it when you see it,” test a rod before committing it to an important piece, and don’t assume a favorite will be remelted.
Chinese import color: Lunar Glass, Tianyuan, and friends
A meaningful share of the color (and especially colored tubing) sold in North America now comes from Chinese producers, at prices well below the domestic houses.
- Lunar Glass is a privately owned Chinese maker whose colors circulate widely through import suppliers; community consensus is that much of the line works from formulas in the style of the original Trautman-era palette, in COE 33.
- Huailai Tianyuan Special Type Glass Co. is an industrial-scale borosilicate producer in Hebei (established 2002) that melts colored 3.3 boro rod and tube across a broad range of hues (company profile), much of which reaches artists rebranded or as generic “import color.”
The honest buyer’s guidance: import color can be excellent value, and plenty of production work runs on it. But batch-to-batch consistency and per-color documentation are exactly the things you give up versus Northstar or Glass Alchemy, so test-fit a rod (work it, strike it, anneal it, check it under a polariscope if you have one) before building an important piece or a production run on it, and be conservative about mixing import color with domestic color in thick work.
The flame-setting conflict: oxidizing-first vs neutral-first
Here’s the genuinely confusing part for buyers, and it isn’t an error on anyone’s part: the two biggest documentation-forward makers give different default flame advice.
- Northstar says most of its colors want a neutral-to-oxidizing flame, and warns that accidental reduction damages much of its palette (flame settings).
- Glass Alchemy teaches the neutral flame as its working default and frames striking around crystal size and heat history (neutral flame tutorial).
These are defaults tuned to each maker’s mix of colorants, not competing claims about physics. Both makers override their own default with per-color notes, which is the real lesson: the colorant in the specific rod decides. The working rule: follow the manufacturer of the rod in your hand, then follow that maker’s color-specific note over their general default. For the full explanation of what each flame actually does to colorants, see flame chemistry: neutral, oxidizing, and reducing.
The same per-color rule applies to kilns: kiln-strike schedules are color-specific, not brand-wide. A published schedule like 1100 °F for 15 to 20 minutes belongs to the one color it was written for. Never generalize it across a maker’s line.
Formats and pricing basics
Colored boro is sold by weight, not by rod count, in a few standard formats:
| Format | What it is | Typical use |
|---|---|---|
| Rod | Colored rod, commonly sold in 1/2-lb increments (Northstar’s standard) | Most work: encasing, sculpting, blowing color |
| Frit | Crushed color in graded sizes | Surface color, blended effects |
| Powder | Finely ground color | Thin coats, shading, color mixing |
| Sample/starter packs | Small assortments across a maker’s line | Testing a palette before committing |
On price: expect steep variation by colorant, not by brand alone. Silver- and cadmium-saturated colors cost multiples of basic transparents because the raw materials do, and import color undercuts domestic color across the board. Prices and ordering terms move constantly, so verify current pricing at the manufacturer before budgeting a palette.
Editor’s note: formats and pricing patterns above are drawn from manufacturer sites as of mid-2026 and change frequently. Treat them as illustrations, not quotes, and confirm with the maker before ordering.
Building a starter palette without wasting money
A sensible first color order ignores the spectacular stuff and buys forgiveness:
- Start with stable colorants: basic transparents and reliable opaques from a documentation-strong maker (Northstar’s quick guide or Glass Alchemy’s numbered families make it easy to know what you’re getting). These tolerate sloppy flame chemistry while your hands learn.
- Buy small. Half-pound increments and sample packs exist so you can test before you commit. A starter palette of four to six colors teaches you more than one of everything.
- Add one striking color deliberately, a well-documented silver or striking color from the TAG line or Northstar’s own strikes, as a learning project rather than a production color. Read striking and silver glass basics first.
- Save the exotic, small-batch, and untested import colors for when you can diagnose your own failures. The boro color troubleshooting guide covers what goes wrong and why.
- Match your flame habits to your palette. If your torch tends to run rich, an oxidation-sensitive silver-heavy order will punish you faster than a stable-color order would.
Torches that give you real flame-chemistry control
Every maker’s guidance assumes you can actually set the flame it asks for. Any decent surface-mix or premix bench burner can run neutral, oxidizing, and reducing flames, but torches with finer mixing control make it easier to hold a precise chemistry while you work. GTT’s triple-mix burners like the GTT Lynx and GTT Cheetah are the usual examples (see GTT triple-mix technology). If you’re still choosing a boro burner, start with the best torch for borosilicate roundup. Color work is exactly where flame control pays for itself.
Key takeaways
- Colorants decide working behavior; brands decide consistency, documentation, and format. Silver strikes and cadmium brights are demanding whoever melts them; cobalt blues are forgiving everywhere.
- Northstar defaults neutral-to-oxidizing and now also produces the TAG line; Glass Alchemy defaults neutral and explains striking via crystal growth; both are overridden by their own per-color notes.
- Momka’s Glass (since 2004) pioneered bright boro color; Parramore Colors offers a consistent, distinctive palette; Molten Aura melts “sandcrafted” color in three tone families; Boro Batch runs limited batches that sell out.
- Import color (Lunar Glass, Tianyuan, and other Chinese producers) is real value with real trade-offs: test before you trust it in important work.
- Kiln-strike schedules are per-color, never brand-wide, and availability churns. Check the maker’s current listing and notes every time.
- Starter palette: stable transparents and opaques first, small quantities, one striking color as a learning project, exotics later.
Related guides
- Flame chemistry: neutral, oxidizing, and reducing flames
- Striking and silver glass basics
- Boro color troubleshooting
- Clear boro quality guide
Sources
- Northstar Glassworks, “Quick Guide”: https://northstarglass.com/quick-guide/
- Northstar Glassworks, “Flame Settings”: https://northstarglass.com/flame-settings/
- Northstar Glassworks, “Reduction”: https://northstarglass.com/reduction/
- Northstar Glassworks, “TAG Rods” product line: https://northstarglass.com/product-category/tag-rods/
- Glass Alchemy, “Setting a Neutral Flame”: https://glassalchemy.com/blogs/the-formula/glass-blowing-tutorial-setting-a-neutral-flame
- Glass Alchemy, “The Glass Alchemy Numbering System”: https://glassalchemy.com/blogs/the-formula/the-glass-alchemy-numbering-system
- Momka’s Glass: https://momkasglass.com/
- KNKX Public Radio, profile of Momka Peeva: https://www.knkx.org/other-news/2020-01-04/this-81-year-old-bulgarian-grandma-is-a-major-figure-in-seattles-glass-scene
- Roger Parramore, “Parramore Colors”: http://www.rogerparramore.com/newcolorco.html
- Molten Aura Labs, “Glass”: https://moltenaura.glass/glass/
- Boro Batch, “About”: https://borobatch.com/about/
- glassglobal company directory, Huailai Tianyuan Special Type Glass Co.: https://www.glassglobal.com/profile/huailai_tianyuan_special_type_glass_co_ltd-52273.html
Editor’s note: brand characterizations (“sandcrafted,” process claims about competitors, historic “first” claims) are the manufacturers’ own statements, attributed as such. Corporate relationships in this niche change hands quietly; the TAG-under-Northstar status reflects Northstar’s own store as of mid-2026. Color availability, formats, and prices change frequently. Verify everything at the manufacturer before buying, and always follow the maker’s per-color working notes over any general guidance here.