@Sicknault knocked out a one-off ½&½ during a batch of Donut Tablets.
The second is a Black Stone Mushroom Straight that slipped into a batch.
Why are they cheap?
Stone Technicians are encouraged to slip 1-offs into the day whenever it seems appropriate. It's a great chance to potentially find something new. At the very least, it's fun to have some unique collectibles available.
You SAVE since we're cleaning house!