Explaining how shares are valued for probate purposes, the London Stock Exchange states:

"The price used in the valuation of quoted stocks or shares is either one quarter up from the lower to the higher limit of the prices quoted, or halfway between the highest and lowest bargains recorded for the day..."

Can anyone tell me the difference (if any) between "the lower to the higher limit of the prices quoted" and "the highest and lowest bargains recorded" and where I might find them listed? Which is quoted in the FT?

Cheers.