Tall fancy letter O surrounded by dainty curly-cues. It looks a bit like an old-fashioned sign post, the kind that used to hang outside of businesses. This vintage black and white image is copyright free and can be used anywhere you need a drop cap O. It’s a little small, but you could remove the letter part and add your own letter or another picture there.
This drop cap was used in the The Merrie Heart A Collection of Favourite Nursery Rhymes. It is most likely a stock image that dates back to at least 1875. Either way, the dates involved put it in the public domain.
This image is copyright free and in the public domain anywhere that extends copyrights 70 years after death or at least 120 years after publication when the original illustrator is unknown.