The Hayagriva-murti-salagrama has the form of a ripe jambu-fruit (rose apple, Eugenia Jambolana), with a face in the shape of an elephant god; it has also longish spots on its body. Lord Hayagriva's chakra that is revealed by separating the two halves, left and right.
Sudarsana-murti-salagrama is round in shape or sometimes oval; there is a single chakra seen at the aperture; and there are spots on the body of the stone.
The Kalki-murti-salagrama is recognized by the line-markings resembling a horse, and the weapon called Kunta (lance). It is white in colour, and has a long mouth. In Salagrama kosha it is mentioned that a Salagrama resembling a horse's head can be identified as Kalki.
The Narasimha-salagrama has an elongated mouth, tawny-hued, a longish chakra and a big belly (viz. Middle portion). This stone is suitable for worship by ascetics. The Lakshmi-Narasimha-salagrama has a chakra on its left side, is black in colour and has spots (viz. Dots). Its worship makes for worldly prosperity as well as emancipation
This is Sarva Kaama Kurma - wish fulfilling Kurma. He too is very rare and there's a sketch of this form in the Salagram kosha book, telling readers what to look for. Well look no further here He is. The Maha-kurma-murti-salagrama is round, shaped like a tortoise, and has marks of vanamala, lotus and discus; its colour is green (viz. Of tree Butea ftrondosa); and it has golden spots.
The Varaha-murti-salagrama is long-mouthed, is blue-black in colour, has an encircling mark of earth, and is distinguished by a shining chakra at the opening. We can see the chakra on the end of His nose; the bobble represents Bhumidevi whom He rescued from the bottom of the ocean
