The phrase "a mixture of joy" is correct and usable in written English.
It can be used to describe a combination of feelings, particularly when expressing happiness mixed with other emotions.
Example: "As she opened the letter, she felt a mixture of joy and apprehension about the news it contained."
Alternatives: "a blend of happiness" or "a combination of delight".
Like many, I did so with a mixture of joy and disbelief.
"Postcard From Iraq," by Thomas L. Friedman (column, May 21), elicited a mixture of joy and consternation.
Ibrox erupted with a mixture of joy and relief as the home players huddled round the goalscorer.
He looked intently at the face of the Virgin, which expressed a mixture of joy, surprise, and sadness.
For Hales, revelling on his home patch, there was a mixture of joy and relief that he should return to form in such spectacular fashion.
Kinks frontman Ray Davies, 72, said he felt a mixture of joy and embarrassment on being awarded a knighthood for services to the arts.
"It was a mixture of excitement, joy, and warmth," she told the Times, in 2016.
Although she claimed her eventual pregnancy to have been 'unplanned' and even stated she regretted having become pregnant before completing her studies, in the context of what had become both a stable relationship and an intense fear of infertility, the pregnancy brought her a mixture of personal joy and social relief.
The hospital called me a taxi, and with a mixture of trepidation and joy, I was able to say to the driver "take me home".
Last night there would have been a mixture of relief and joy across this cricket-mad country as more than a billion people celebrated the extraordinary achievements of one of world's greatest sportsmen.
It was greeted with a mixture of relief and joy by politicians from all parties in West Germany as the end of months of uncertainty, giving a new impetus for private investment in East Germany and providing stability for its 16 million citizens.
