This was worked with #20 Thread Coats & Clarks Big Ball and #10 hook and measures 9¼ inches point to point. The pattern is from
Coats & Clarks Book No. 285 "All Time Favorites" published in 1980.
I believe this pretty old pattern may be in the public domain, it was once featured in "Old Time Crochet". I haven't found the pattern on the web yet.
The 1980 patternbook called Red Heart Lustersheen, a size 5 hook and measured 19 inches across. I made the pattern once with a cotton and rayon yarn, and a size 2 hook. It measured about 23 inches across.
It works up quickly. If you want to make an elegant doily and time is short, this is a good choice. It's best worked firmly so the pattern is well delineated.