rudraksha

 white - brahmans rudraksha

red - kshatriya

tamrind seed color - vysya 

black - sudra should wer for favourable result

sinks in milk and water

Light rudrākshas or tender rudrākshas should not be worn

When a rudrāksha is placed below a copper spoon and if a copper plate is kept underneath, if it rotates clockwise like a sāligrama2 then it should be understood that it is of good quality. Some rudrākshas rotate anti-clockwise. They bring poverty. So householders should not use them. If householders use them, then bad effects like death of wife, dissolution of family and renunciation from family can happen. Ascetics may, however, use them.

their sins are destroyed, and all their desires will be fulfilled

1 mukha is form of shiva

Five-faced rudrāksha is the kālāgni form of Rudra

9 rudrakshas is form of kapila with 9 kalas

difficult get 

sripada_srivallabha_charitamrutam.pdf