Complex sentence: While the celesta is not overly common in more popular forms of music, it's been used now and again such as in a number of recordings made by Frank Sinatra for Columbia in the 40s, most notably "I'll Never Smile Again".
Split into simpler sentences: While the celesta is not overly common in popular music, it's been used now and again. A number of recordings made by Frank Sinatra for Columbia in the 40s feature the instrument, most notably "I'll Never Smile Again".