While taking a break from a fiendishly difficult trellis stitch leaf, I decided to move ahead with the remaining acorns.
All the acorn bodies are done in Ceylon stitch, which looks kind of like knitting, as can be seen in this photo of completed acorns stitched in silk. A stitch diagram can be found here.
The next remaining acorn called for the nut section to be stitched in silver tambour, and here's where things got dicey. Metallic threads are notorious for obnoxious behavior. . . and that was certainly the case here. This photo shows the kind of schenanigans you can expect (see the spontaneous kinked section towards the right).
Complicating things further, between the size of the stitch and the shine of the thread, it was almost impossible to see the stitches while working. (Amazing now clear it all is in the blown up photos.)
In any case, after cutting out two unsuccessful tries, I decided that I needed help. . . which I provided myself by tacking down each stitch as I worked. While VERY time consuming, this did make the stitched loops lie flat and stay still instead of kinking up and semi-floating above the fabric. The photos show the individual loops tacked down as I worked, and the finished product with the tacking stitches removed.
So. . . cheating or not. . . the nut of the acorn is done!