Randgold Resources has shifted from the FTSE 100's biggest risers to lead the largest fallers.
On Monday it announced that it was being taken over by Canada's Barrick Gold, sending its stock price higher.
Today, however, its shares have dropped 2.3% to £53.36.
Conversely Kingfisher, owner of DIY-chain B&Q, is the biggest blue chip riser on Wednesday morning, up 2% at 260p.
The wider FTSE 100 is down 0.17% at 7,494.86.
AA is the biggest faller on the FTSE 250, down 6.8% at 110p, after revealing a sharp fall in interim profits.
PZ Cussons' stock rose 2.76% to 236 despite continuing challenges in its Africa business.
It said its quarterly results were in line with expectations.
The FTSE 250 is down 0.17% at 20,425.28.