I think those are simply ISA or SIPP transfers : two trades just seconds apart, one is a sell from a non-ISA account and the other is the purchase into the ISA (or SIPP) account.
I see what you mean about the missing bar charts though.
The other thing about COAL on GS20 is that the price always shows as $0.0030. It has never shown anything different for at least a year. In reality COAL has varied over that period from about $0.0010 to $0.0035 (currently $0.0032). That's another reason why I don't believe any of the figures showing on GS20. Its unbelievable that this site can show nonsense figures for months and months on end and nobody fixes it.