I was researching some parts on a board, and I found some off looking capacitors ... it turns out they are silver bearing !
They are called "silver mica capacitors " ,they have a pretty unique look to them and are usually used for medium and ( relatively ) high voltages ...
http://www.rf-microwave.com/uploads/...er_mica_01.png
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http://g03.a.alicdn.com/kf/HTB1dB_1K...-capacitor.jpg
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http://www.partsconnexion.com/media/...s/ru-smica.jpg
