Pattern weights are great to use with delicate fabrics when you don't want to make holes with pins or when you need to hold things down for a quick cut.
Commercial pattern weights are usually metal rings but anything that successfully holds the pattern down works. I've used drinking glasses, soup cans, and any knickknack close by and in reach. It was finally time to just get it done and make some.
I cut 3.5" fabric squares and sewed with a 1/4" seam allowance for a finished size of 3". Here's the twist -- I used small garden rocks leftover from a landscaping project to stuff the squares!
These are so handy and useful that I wish I had gotten around to making them years ago. I still will use a few pins on the grain line (old habits die hard) but mostly it's these pretty little things holding the pattern down while I cut.