Although could easily be book hype, as there has got to be an entertainment factor behind the book, I believe To Live Outside the Law a pretty decent book on Operation Julie had some bits on how they did microdots at the time. As far as I remember it was basically gelatin with I'm assuming LSD dissolved in it already or stirred in etc. This was then spread over a tray with the microdot shapes basically embedded in the tray, the gelatin paste went over, dried out and then microdots were popped out. Have heard also before that they are pressed just like any other pill. The ones I've came across in recent years have varied in size slightly and normally presses on a industrial scale are going to be same size/weight I'd assume?
Hopefully if someone has access to the book and know what I'm talking about they could quote the section. They are a lot harder to handle too compared to just simple perforated blotter due to their extremely small size. Saw Peruvian Torch seeds also a while back and they actually looked exactly like microdots, so was wondering if this could be attributed towards the whole mescaline as a microdot myth/bullshit, alongside standard dealer talk.