Raw Botryoidal Gloss Hematite Mineral Crystal Radio Diode AB

Description

Botryoidal Hematite Mineral Crystal Radio Detector
Raw Crystal (Not Cast)
Freshly sheared Crystal exposing at least one freshly sheared surface
Customer Comment...
"
The
Botryoidal Hematite
is one hot crystal"
High luster Gloss Botryoidal Hematite Crystal Detector
Newly Identified Experimental Mineral that outperformed the tuning stability of every mineral that I have tested to date.
The Crystal is very hard and with a Gloss Surface appearance
I was able to find a Hot Spot in as little as 15 seconds
Always Freshly Sheard Crystal to expose at least One Fresh and New and pristine whisker contact surface
17mm x 7mm x 9mm
FACTS ABOUT OLD SCHOOL CRYSTAL DIODES
Not every contact position on the Galena crystal will perform, so fiddling with the ‘cat's whisker’ to find a sweet spot does take patience and skill.
Cat Whisker:
The "cat whisker", a springy piece of thin metal wire, formed the metal side of the junction. Phosphor bronze wire of about 30 gauge was commonly used because it had the right amount of springiness.
Cat whisker detector:
It consisted of a pea-size piece of crystalline mineral in a metal holder, with its surface touched by a fine metal wire or needle (the "cat whisker"). The contact between the tip of the wire and the surface of the crystal formed a crude unstable point-contact metal–semiconductor junction, forming a diode. The wire whisker is the anode, and the crystal is the cathode; current can flow from the wire into the crystal but not in the other direction.
Having a lot of patience and a steady hand are needed when you listen with a piece of the rock. But this can also be very rewarding when you can hear the first station using a cats whisker detector.