Quote from: 'JeffH' pid='112113' dateline='1507165079'Firstly Ian (I presume), :welcome: to the forum.

I will kick this off with what I know and see what others think.
•Not mentioned in Renniks or Maccas so unlikely to be a recognised variety. I have no recollection of a "no SD" being mentioned previously.
•I just checked twelve of these (high grade noodling finds) and found two without a discernible SD. Some others had very faint SD or part missing.

So probably not that uncommon.

It could be a die fill. Any chance of a photo?

Thanks Jeff, sorry i haven't been able to work out the attachment thing yet.

hi i've only recently started looking at coins but came across a 1978 20c coin that has no visible sd mark.  Is that common?