Pyrex 401 Blue Primary Colors 1 1/2 Pint Mixing Bowl, Smallest Bowl of the Nesting Set
The Pyrex 401 is the blue bowl, and the smallest, of Corning's Primary Colors nesting mixing bowl set (401 blue, 402 red, 403 green, 404 yellow). It is white opal glass with a medium true blue fired-on exterior, a white interior, steep flared sides and a raised band below the rim. Embossed on the base are 401 - 1 1/2 PT, TRADE MARK, a mold number, PYREX, R in a circle, MADE IN U.S.A. and OVENWARE. This numbered version dates from 1950 or later; the first Primary Colors bowls of 1945 to 1949 are unnumbered with a larger foot.
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The smallest bowl in Pyrex's Primary Colors set
Primary Colors was Pyrex's first opal ware mixing bowl set, introduced in 1945 with blue, red, green and yellow bowls nesting from smallest to largest. The first bowls carried no model numbers; after a 1950 redesign of the base they were numbered 401 blue, 402 red, 403 green and 404 yellow. Smallest of the four, the 401 is marked 1 1/2 pint.
Small blue Pyrex bowl with a white inside and a raised rim band
The Pyrex 401 blue Primary Colors mixing bowl is the smallest bowl in Pyrex's four-bowl nesting set. It is white opal glass (milk glass) with a fired-on color coat on the outside only: blue, a medium cerulean or true blue, glossy when new. Inside, it is plain white with a faint blue-gray cast. Rising steeply from a small base, the sides flare out to a wide, rounded rim, so the bowl is deep for its size.
No printed pattern appears. Its one design detail is a raised horizontal band, a shallow step or ridge, that circles the outside about an inch below the lip, giving the rim a collar. The lip itself is rounded and left white along the very edge.
Underneath, the base is a raised white foot ring with no blue color on it. At the center, the base is embossed in raised lettering arranged in a circle: 401 - 1 1/2 PT arched across the top, TRADE MARK arched below it, a small mold number (29 on this copy) in the center, PYREX in tall, plain block capitals across the middle, the registered R in a circle under it, and MADE IN U.S.A. and OVENWARE curving around the bottom. The three-digit 401 number marks the version made from 1950 on; the earliest Primary Colors bowls of 1945 to 1949 have no model number and a larger rimmed foot.
On this copy: not measured; it fits in an adult hand, roughly 5.5 to 6 inches across. The blue outside has heavy utensil marks and gray scratch lines, small white flecks of color loss at the rim and band, and dishwasher dulling. Inside, the bowl is clean and white, with light wear in the bottom. No chips or cracks were seen. It carries mold number 29.
- Maker: Corning Glass Works, Pyrex
- Shape: Deep round mixing bowl, steep flared sides, raised band below the rim
- Material: White opal glass (milk glass) with a fired-on exterior color
- Color: Blue, a medium cerulean or true blue outside; white inside
- Capacity: 1 1/2 pint, marked on the base
- Base: White raised foot ring with no color
- Marks: Embossed 401 - 1 1/2 PT, TRADE MARK, mold number, PYREX, R in a circle, MADE IN U.S.A., OVENWARE
- Set: Smallest of the Primary Colors nesting set: 401 blue, 402 red, 403 green, 404 yellow
- This copy: Not measured, about 5.5 to 6 in. across; mold number 29; heavy utensil marks and scratches, small flecks of color loss, no chips
Base, embossed in a circle: 401 - 1 1/2 PT TRADE MARK 29 PYREX ® MADE IN U.S.A. OVENWARE
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About the Pyrex 401 Blue Primary Colors Bowl
How do I tell how old my Pyrex 401 blue bowl is?
Check the base. A bowl marked 401 was made in 1950 or later, after Pyrex redesigned the base and added model numbers. The first Primary Colors bowls of 1945 to 1949 have no number and a larger rimmed foot.
What size is the Pyrex 401 bowl?
It is marked 1 1/2 pint on the base and is the smallest of the four Primary Colors nesting bowls.
What colors came in the Pyrex Primary Colors set?
Four bowls: 401 blue, 402 red, 403 green and 404 yellow.
Is my Pyrex 401 blue bowl valuable?
Used 401 bowls listed on eBay run about $18 to $28 before shipping. Bright color with few utensil marks brings more than a scratched, dulled bowl like this one.