The ‘Celtic Horse’ seen on the ‘primitivist’ coins of the Iron Age often showed interesting design characteristics related to concentric circles and points. These became prominent elements of insular Celtic coin designs and regional rock-art, such as that seen in Scotland among the ‘Picts’. The design here is taken from a 2000 year old coin of the Dobunni in my collection (W. Britain).
‘Aberlemno 1’ pictish stone (Angus, Scotland). The ‘double disc’ motif appears with the ‘z-rod’ and the mirror: symbols of rotational and reflectional symmetry. The serpent at the top demonstrates that this symbolism is expressive of the Atlantic otherworld beliefs…
Note the rotational symmetry seen in the horse-design of this coin! Wiltshire ?Dobunni 1stC BCE. Photo: (c) 2014 http://www.celticcoins.com – Chris Rudd
The Atlantic Religion 
I am mystified by the symbolism of Celtic coinage. Puzzles. You compare them to Miro an Picasso. I had not thought of Miro, so true. I wonder how the makers of Celtic coinage allowed themselves the freedom of such extreme stylization, to the point of abstraction? Miro and Picasso had their roots in the classics, and their art grew as a response, or escape, of an earlier school of thought. Was Celtic symbolism perdicated on another style? Were they trying to disguise the message?
Esotericism, certainly. The imagery of La Téne era art is full of movement and dynamism and the potential for immanent transformation, which were likely congruent with the spiritual, cultural and unitary political beliefs underpinning the pan-European and Eurasian ‘Celtic Golden Age’ that reached its climax between the 4thC BCE and 1stC CE, and explains why there is a Galicia in both the far west and far east of Europe, a province of the Near East known as Galatia (surrounding modern Ankara in Turkey), and possibly even a place called ‘Gallilee’ further south 😉