Shaligram Shila or Salagrama Stones are worshipped as a natural form of Bhagvan Vishnu. Here is a brief not on how to identify a Good Shaligram Shila. This will help you in avoiding cheats who sell fake Salagrama Stones.
A good and auspicious Salagrama is one which has a Chakra, which resembles a naga (cobra) reposing in a spiral.
The spirals in the chakra in the Salagrama should have in them delicate traceries running across them.
Those salagaramas which are the size of an amalaka fruit (gooseberry) or smaller are considered highly effective.
Salagrama may be of the following colors – brownish black, green, white, red, blue, dark brown, jet-black, yellow or multicoloured.
Salagrama Stones That Should Be Avoided
Badly mutilated, rough surfaced ones, having large number of holes, scarred with many lines, unusually large sized, having only one loop in the spiral, burnt, very red, those with several chakras in a line should be avoided.
Source – Elements of Hindu Iconography Part 1
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