Description of Sadashiva from Kalika Purana.
The following is a description of the five faced Shiva taken from the 51st chapter of Sri Kalika Purana, the description doesn’t match the picture exactly unfortunately but it paints a great mental image:
Verses 137-141. Mahadeva (Shiva the great God) is with five faces, with a huge body, and matted hair, the charming crescent moon on His forehead, having ten arms and clad in tiger pelt, He wears serpents as ornaments. A blue line of poison sits at his throat, shining with a necklace of serpents, His hair is tied with a snake, His body shines like the rays of the moon. Smeared in ash with three eyes on each face, He covers Himself with an elephant hide and sits on a bull.
Vs 142-145. The God has five faces- Sadyojāta, Vāmadeva, Aghora, Tatpurusa and Iśāna. Sadyojāta is white like crystal, Vāmadeva is yellow-charming like a moon beam, Aghora is indigo-dreadful with big teeth, Tatpurusa is divine red and Iśāna is greenish-always auspicious.
Vs 147-148. One should meditate on Shiva as the possessor of eight kinds of powers* holding a lance, trident, club (the text says a club of the shape of the leg of a bed!), the gestures of blessing and fearlessness, a string (aksa-sūtra), a lotus, serpent, drum and lilly.
*The eight powers or qualities are listed in Shiva Mahimna Stotram:
भवः शर्वो रुद्रः पशुपतिरथोग्रः सहमहांस्तथा भीमेशानाविति यदभिधानाष्टकमिदम्।
अमुष्मिन्प्रत्येकं प्रविचरति देव श्रुतिरपि प्रियायास्मै धाम्ने प्रविहितनमस्योऽस्मि भवते॥२८॥
Bhava, Sharva, Rudra, Pashupati, also Ugra with Mahan, furthermore Bhima and Ishana, these are eight appellations of the Lord, each of them the srutis individually expound. My salutations are to the dear abode in which these names are laid i.e. to one who bears these names.
The essential qualities associated with these names are:, Bhava - Existence, Creation, Sharva - destruction, Rudra - Dispeller of Sorrows, Pasupati - Lord of all beings, Ugra - The Fearsome, Mahan or Mahat i.e. Mahadeva – The Supreme, Bhima - The Tremendous, Isana - The Directional ruler. Linga Purana 2.13.10-18 also elaborates these eight qualities in detail.