There are two Inscriptions of Lajaka Tissa a son of King Sadatissa who reigned the nation of the Sinhala in our Island called Lanka Dipa according to our ancient text the Mahavansa and Dipavansa. These are menioned by MR M.H. Sirisoma the a past Archeological Commissioner. Perhaps these two inscription may some day provide more infomations or deductions by the experts on art ,as to why symbols of managala lakuna[ Paranavitane has given the names which were perhaps used by the sinhalese of the first century BC for these symbols] to were placed on coins.
The inscription are described in detail by Dr S Paranavitane in Inscriptions of Ceylon Volume II part I, 1983.
Th first inscription is from Rajagala and has an symbol which is not clear, but Mr Sirisoma thinks it may be Dhrama Chakra or Triratna or a Sripada , an Footprint of the Buddha. In most Sri pada’s found in Sri Lanka , most of the minor symbol [ click to read about symbols found on coins] are found on our coins as well as in buddhist art of ancient ruins of temples.
Of course they were symbols found on most ancient civilisations and the found on in India , but the Buddhist and Jainism adopted them and these are found exclusively on Buddhist and Jainism monasteries. They are also found in Hindhu temples, but most of these Kovils are of later dates. These are discussed in details under Coins of Ancient Srilanka in the Blog – sirimunasiha.wordpress.com
The second Inscription mentions two symbols gives the names of the Bodhi Tree and Asana or throne used by the sinhalese in the first century BC and associates these symbols with names of King lanjaka Tissa the son of king Sadatissa the brother of King Dutugemunu. This offering to the Vajrasana or the crystal seat on which Buddha sat was in vogue during this period.Was this concept in some way useful in the acceptance of these symbols as those of the authority of the Issuer or the ruler of the country??.
Incidently the layers in which over five types of Bodhi-Tree in Enclosure and Railed SwastikaCoins which is found in Lanka Dipa and has been carbon14 dated to this period during all excavations conducted on major sites here. The Asana or the throne on which Buddha attained enlightenment is also by side of Bodhi tree or the Railed Swastika. All King were treated as future Bodhisttva’s , perhaps the the Asana on coins may also have been considered as the Sinhasana or the throne of the Sinhala. Comments both positive and negative on this speculations are welcome, as they will most certainly enhance Numismatists knowledge. These symbols is not something novel to the Island, but the Tree in Enclosure is associated with Drum like Asana on the earliest Punched Mark Coins having the Tree in Enclosure perhaps of King Kalasoka[ No 369 of Gupta & Hardekar] of India perhaps minted during the First Buddhist Council [ Mahavansa].