The rather sad reconstruction of the Lansdown ‘sun disc’.
Its centre appears to have been a boss surrounded by smaller bosses, chevrons, concentric line-infilled circles, more bosses and more infilled concentric circles”. Ashbee also goes on to say as a word of caution “as tentatively, and perhaps unjustifibly reconstructed”. This sun disc was found in bits but the photograph of the bits do have many of the features described. He goes on to say that it has “affinities with the disc on the Trundholm sun disc”. Other types of sun disc found in this area 1) two at beaker grave on Mere Down (Hoare1812-19) and Monkton Farleigh (WAM L11
270), describing thus; small, perforated, cruciform ornamental discs.
Taken from Earthen Long Barrows – Paul Ashbee
That is indeed quite a jigsaw puzzle. But presuming it was disc-shaped, and symmetrical, maybe not such an 'unjustifiable reconstruction', maybe that's a bit too pessimistic of him?
It is a bad photo to start with but your Farleigh Wick gold disc reminded me, and to be honest you can see the 'pattern' of it, so maybe Ashbee is wrong. Mike Aston made a very symmetrical drawing as well, which is similar to yours, was not sure whether to put it on....