Watch List notes:

Celtic, Atrebates and Regni, Tincomarus, (c.25 BC-AD 10), silver Unit, 1.24g, 'Bull Right' type, laureate head right, c behind, rev. bull right, tin above, co below (ABC 1115; VA 381-1 var.; S.85 var.), dappled patina on frosted surfaces, scratches to bust, full and round, well centred reverse, very fine/good very fine, rare variant with CO behind forelegs. Subject to 20% VAT on Buyer’s Premium. For more information please view Terms and Conditions for Buyers.
provenance
Bt. Highfield, 22 April 2007
Found Chichester, Sussex

The C behind the laureate bust doesn't appear to be mentioned in ABC.
Estimate: £200.00 - £300.00