I would assume determined as an asset value or market value at...

I would assume determined as an asset value or market value at the time you acquired them. Closing price on that day being $1.21. No different to acquiring for example deceased estate as an asset. The market value is determined from time of death of the holder before passing over to the new holder. Then from that point in time Realised gains or losses can be determined as Capital gains.
Also don’t think it should be confused as a dividend. A dividend is a distribution from net company profits derived from revenue income generation.