For Rocky, here's a view of the living room.



Back to the Chemex, I brewed with it this morning, using their brand name pre-folded white filters. The filters are slower than I've seen with others, so the coffee is richer, but it also means that next time I'll coarsen the grind for the longer steep. The coffee also isn't as clear as with other filters, so I wonder if it lets through very fine particles to enhance the rich flavor. In that case I expect that it would still absorb coffee oils. It doesn't taste gritty. I see that this isn't the best method for people who want very hot coffee, but I like the flavor more as it cools, so I'm fine with it. As others have written, glass tends to dissipate heat compared to an insulated carafe.

Ah..I also have my Chemex..but not use too often..

drgary wrote:For Rocky, here's a view of the living room.

Gary,

Thanks. I love the rooms and the photographs.

Rocky

Here is a blog post from Venia Coffee (now Berry Tree Coffee Roasters) on the earliest Chemexes. It includes patent drawings.

I have seen online auctions of embossed Chemexes where one that was said to be from the early 1940s had a small, white engraved patent stamp across from the embossed patent on the other side. Another attributed to the early 1950s has a small blue patent engraving across from the embossed patent. Does anyone reading this know of a collector's guide that differentiates the early production runs and that might have a clue about how many of each were made? Embossed early Chemexes come up for sale fairly often. They're priced at a premium but often aren't more expensive than new hand-blown units.

The earliest current design Chemex submitted by Schlumbohm to New York's Museum of Modern Art has the engraved brand and patent across from the embossed patent, but I can't tell from the photo whether the small engraving is white, blue or some other color.

Good news! I've just acquired a blue logo engraved, patent embossed Chemex and will be posting about it in this thread when it arrives. Is it hand blown? Not sure, nor is the seller. But it is obviously one of the early ones and is larger than my current one.

What a wonderful peak into your childhood home. Everything is so stylish and crisp and inviting! I could move a few levers in and feel right at home all this many years later. Thank you for sharing Gary. I still can't see the Chemex but great score.

Collette at the Chemex customer service team responded quickly to my request to better identify this embossed brewer. Here's what she wrote along with congratulations:

"It looks like you have a 13 cup handblown carafe. With that embossed patent and logo, this is definitely from the earlier years of Chemex manufacturing. Chemex was invented in 1941 so we don't feel that this is necessarily from the 1940's but more likely from the late 50's/early 60's. What is unique with your particular brewer is the blue stamp. Most vintage brewers with this stamp are green and not blue. This stamp may be blue because it is an earlier production than the green stamped ones that came later. This is also why we feel this may be a 1950's brewer versus later years."

I didn't know until fairly recently that earlier Chemexes had a patent mark embossed in the glass. These are more collectible than later versions. Across the bowl from the embossing, they have a manufacturer's engraving. This configuration of embossing and engraving is seen in the earliest 1941 8 cup version in the collection of the Museum of Modern Art (MOMA) in New York City.

I've seen embossed Chemexes listed for sale as engraved in white, blue and green. The green ones are found more often than the other two. Later hand-blown versions without the embossing are also engraved, but on the bottom. After acquiring blue and green stamp versions of 13 cup embossed Pyrex Chemexes, I found differences worth documenting for other collectors. The blue stamped Chemex is on the left. According to Collette at Chemex Corporation, the blue stamped version is earlier, dating from the late '50s or early '60s. I don't yet have a date on the green stamped version.

Added 12/1/17: More correspondence with Collette led to her asking some of the company owners about the blue/green stamped sequence and manufacturing dates. They told her that embossed Chemexes were probably made in the 1940's to 50's, not later. They told her blue or green stamps were most likely from the 1950's to '60s. That suggests the white stamps were earlier. The owners told her the green stamp probably preceded the blue, although at one time they may have been manufactured simultaneously. The details compared below suggest to me that there is a cruder version of the embossing that was earlier and is seen in my blue-stamped version. The "crude" version has the name making a full arc, so the "C" and "X" are horizontal (see embossed versions compared below).



I believe all of the embossed ones are hand-blown, and I've been assured by Collette that both of mine are. Each shows slight imperfections suggestive of a manual process. The green stamped has a couple of tiny bubbles inside the glass. The blue stamped one has an oblong pooling of glass within the round circle of the mold on the bottom. Collette says such variations were more common in earlier hand-blown versions. Here's a photo edited to highlight that.



The blue and green stamps have identical text, but the blue one is lower on the bowl.





The molds were changed from the blue stamp color to green. Two differences immediately stand out. The blue stamped version is 25.8% lighter than the green one at 892.6 to 1202.6 gm. The green stamped feels very substantial at more than 1 kilogram. The blue-stamped has a slightly rounded bottom without footings, versus three footings on the green one that sits rock-solid level. (Looking at photos on the Chemex Corporation site, the modern hand-blown 8 and 13 cup versions don't have glass footings like two of my vintage ones. Here's a photo comparing the bottoms of the two 13 cup brewers.



At first I didn't like that the blue stamped Chemex rocks slightly on the counter. Then I realized it works very well for using the "Rao spin" brewing method, where the coffee slurry is swirled to create an even extraction marked by a flat bed of spent grounds, and even though Scott Rao acknowledges he didn't invent the method. You can get the same effect by sliding a flat bottomed brewer, but it's not as easy. Here's a video showing how the blue stamped Chemex rocks. It's very easy to make this rocking circular.
13 cup Chemexes have two convex buttons molded into the glass, which must be where the liquid glass enters the mold. The blue stamped marks are lower on the base and closer together.

Blue



versus green



The embossings are also slightly different, although their diameter seems identical. These are easier to see than to photograph. The text on both reads:

Chemex
Pat
2241368

The blue stamped version spreads the word, "Chemex" across the top, with the "C" and "X" facing sideways and is just a bit further from the top rim. The later, green version has the letters more compressed.

Blue



versus green



There's a visual illusion when viewing the 13 cup versions next to an 8 cup 1970's Auer Glas German hand-blown Chemex. The funnel on the 8 cup looks larger, but they are the same dimension. This photo inverts the 8 cup over the 13.



Their heights are identical at 11 1/4 inches. Other than the differences noted above, their shape and other dimensions seem identical. Which is more valuable, the earlier, lighter one that may be rarer or the later, heavier one? I don't know. I tend to like the one that rocks because the slight roundness in its bottom makes it easier to brew using my preferred method. I also really like the hefty feel of the later one.

^ Put those on the shelf!

Very nice finds and very interesting history. Thanks for unearthing the Chemex background.