The identifying attributes are pinched bun like hairdo and the butter churner in the right hand. Here Krishna is standing in Samapada with his right hand holding the butter churner and left hand holding the ends of the rope used to turn the butter churner. As usual, the ornamentation is profuse, head (on the sides), ears, shoulder, wrist, arm, necklaces, chest, waist and ankles. He is wearing an ankle length lower garment, with side flares, and his upper body is bare.
The main deity, Krishna, is made of copper as compared to Prabhavali and Bhadrapeethan. They seem to be made of brass/bronze. This is not unusual as copper is ‘higher material’ compared to brass/bronze. See Anjaneya on this website.
Prabhavali has Makara, Naga canopy and Kritimukha (face of victory). See the above picture of Prabhavali. This is typical of bronzes from Karnataka, Telugu speaking area (Andhra) and Tamil Nadu.
The deity slides into the slot in the Bhadrapeetham, a feature typical of Karnataka region.The floral pattern, outer side, of the prabhavali, suggests Maharashtrian influence.
In the base and back of the prabhavali, there is inscription ‘Madhav’ in Devnagari script. Madhav is one of the names of Krishna. It is quite likely this was made outside Udipi region, most likely in the Western Deccan region as an object of worship.
Locally this form of Krishna is known as Kadegolu Krishna. Kadegolu refers to the butter churner in his right hand. Prof Gururaja Bhatt’s book, Studies in Tuluva History and Culture has few examples of this form (Page 330 for text). All the examples in that book are dated to the 16th century.
The patina is deep and there is worship related wear. There is some oxidation, mainly in the deity. It is very heavy, especially the Bhadrapeetam and Prabhavali. The height of the bronze is about 24.5 cm and the main deity is 13.5 cm in height.
For comparison, I have shown an image of Udipi Krishna bronze (left as you see it, the height of about 8 cm) below. That bronze is contemporary. A comparison shows regional and time-sensitive differences.