Constantine I  AV Solidus of Trier, struck 320 AD. 4.24g, 19mm.

Obv. CONSTANTI-NVS PF AVG, laureate head right. 
Rev. SECVRITAS REIPVBLICAE, Securitas standing facing, head 
right, hand on head and leaning on column

Mintmark PTR.

RIC VII 246; Alföldi 456; Depeyrot 27/3; Sear 15703 (value £775-£2,300).

Offered on ebay for US $12,777.00 by terrasinisteve, August 2012.