The Rare Unmarked Vintage Pyrex Dish You'd Be Over The Moon To Find At A Thrift Store

On the bottom of almost every piece of vintage Pyrex is a backstamp, an identifying marker that lets you know the brand name and other pertinent details about the dish. Since backstamps change over time, studying the markings on the bottom of your Pyrex can clue you in to when the piece was made, and in some cases, the model number and size. A backstamp is one way to identify valuable Pyrex at the thrift store.

Except when it isn't. See, there's one Pyrex pattern that's rare and in-demand, but that doesn't have a backstamp, or in fact, any markings on it — dubbed the "New Mexico" print. Its lack of a backstamp hasn't diminished its value in any way. If anything, those missing markings have only increased the pattern's value, which is estimated to range from $2,000 to $6,000.

The New Mexico design is available in three colorways — white with blue, black with white, and yellow with burnt orange — and only in the 1.5-quart oval casserole. Not much is known about the mysterious pattern, but it's possible it was a test product that was never officially released to the public due to flaws in the screenprint. Since it doesn't bear the Pyrex name, it could be easy for someone unfamiliar with the pattern to pass it off as a just a knock-off, even though it's a valuable Pyrex dish you don't want to overlook.

Pyrex New Mexico definitely falls into the "holy grail" of valuable kitchenware finds category, but, since it's not marked, it can be trickier to determine if what you're holding in your hands is the real deal. The first thing to do is examine the pattern and color. The background will either be white, yellow, or black.

Then, take a look at the design on the dish. It will have two rows of alternating starburst-like circles around the circumference. On the yellow casserole, the design is in a burnt orange or brown color; on the white dish, the design is in a brilliant blue; and on the black dish, the design is in white. The pattern looks somewhat similar to the small Town and Country pattern, but Town and Country dishes have a single row of embroidery-like stars and an orange or yellow background. They'll also have the tell-tale Pyrex marking on the underside.

The other thing to examine if you think you've come across Pyrex's New Mexico pattern in the wild is the dish's shape. New Mexico was printed on a 1.5-quart oval casserole, model number 043. The dish may or may not have a clear glass lid with it — having a lid increases the casserole's value, but it's common for lids and bowls to get separated over the years. Since it only has a volume of 1.5 quarts, the dish will be on the small side, about 7.75 inches wide and a little over 3 inches tall.