Skip to product information

The SG-1

300mm Stone Grinder, an innovation 2,000 years in the making
Regular price $54,749 USD $
Regular price USD Sale price $54,749 USD


Welcome to the past future of grinding: The SG-1 (Stone Grinder 1). We took a cue from the local ancestors around our R&D facility in Japan to get back to where it all started, and we were as surprised as anyone to realize that they were already ahead of most modern baristas over a thousand years ago.

The SG-1 is limited to a production run of a single unit. Who will become the lucky chaperone for the future generations? Or will we even allow ourselves to sell off this piece of history? Can history even be purchased, or is it just an existential question we ask to amuse ourselves?

Items Included

 SG-1 Grinder
Works anywhere in the world. Predates CE and UL certifications by several hundred years.

  • Top and Bottom Stones (more accurately referred to as "querns") 
  • Solid Oak and Horse Hair cleaning brush. Period accurate. Actually we just bought from Muji but will throw in for free.
  • Felt Pad for protecting table top surface. Not period accurate, but your table will thank you.

Historical Notes

The SG-1 is a fully functional and perfectly preserved example of a rotary quern grinding millstone from the Yayoi (300BC) through Meiji (1912) periods in Japan. While they were primarily used to mill rice into rice flour, their usage widened into various types of grain flour and, today, specialty coffee.


You may read more about ancient grinding stones of Japan here.


The SG-1 is currently available in extremely limited supply. By "limited" we mean a single unit. One. Uno. Ichi. Un. Ein. Doesn't get any more exclusive than this.

Recommended Pairings

01 of 00

The EG-1

Regular price $4,095
Regular price Sale price $4,095 USD
If you're feeling more Taycan than Horse-and-Chariot.


Regular price $365
Regular price Sale price $365 USD
Pair the past with the future and never look back
01 of 6

The SG-1: Truly Timeless Grinding

We let our ancestors do the heavy lifting, but we made it desirable.

Technical Specifications & Details


Grind Retention

We won't lie. They didn't have this one fully figured out. In our testing, we put in 20 grams and got just 8 out. Some may call it wasted effort, but with the forearms you build you’ll be able to throw away your juice squeezer.

Grind Retention


290mm diameter, 275mm height, 40Kg pair weight.

Grind Retention

Maintenance & Cleaning

The cleaning process for the SG-1 is easy.  Drink a highly caffeinated energy drink, flex biceps, and lift top stone off and flip over. Inner grooves (or more correctly, "furrows") can be cleaned thoroughly in seconds with the included boar hair brush.

Grind Retention

Burr Alignment

No need to. Ever. Let the weight of the stones work for you, and focus instead on how you’re channeling the ancient gods in your latte art.

Grind Retention