I've had conversations with Chris and Bruce about these. Large quantities BS will most likely be interested in but it's the sorting and making sure you have the correct Tantalum epoxy caps. Most are yellow, orange, red, green and blue; green and blue being older/rare. All have a vertical line, or a slight "L", and a "+" , next to the line. Older caps have dotted or hashed lines but still carry the "+" or "K/M±%". Don't always look for the "K or M" on tantalum though, can get confused with other types accidently. Older capacitors will only have a positive mark, making it harder to identify because it's closely to other types of capacitors. Be observant. They will almost always look like a teardrop or water droplet.
Tantalum comes in axial versions too, being the most abundance contained tantalum but are difficult to identify. All found in hybrid and older applications.
If I'm not mistaken, They only want the yellow, red, and orange.
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