This particular radio is considered a favorite among collectors due to some of its unique features including an internal ferrite antenna and fine adjustment dials that allow better separation of incoming signals. It is so popular that if you are not lucky enough to find a used one at a reasonable price you can purchase some current reproductions that are available for quite a bit more than the original $8.00 cost.
You can see from the image of the front of the CR-1 and the schematic below that this radio has two adjustable capacitors, one for antenna tuning (C1) and one for detector tuning (C2). There is also a switch (S1) that can add 0, 350 or 700 uF of capacitance to adjust the antenna tuning for a high, medium, or low part of the AM band. The detector is a glass encapsulated germanium diode.
References & Additional Resources:
Blog post by crystal radio enthusiast Steve, VE7SL.
https://www.amateurradio.com/the-enigmatic-heathkit-cr-1-crystal-radio/
Scott’s Crystal Radios describes the duplication of this radio from scratch.
http://oldheadphones.com/crystal/info/heath.htm
Full description found on Radiomuseum.org
https://www.radiomuseum.org/r/western_44001_1.html