Did you ever find the maker of this mark? I have four cups with the same mark (although I have been debating on whether it is a K or an R) and haven't been able to find anything.
The size usually, or maybe the code for the shape.
If it is on the bottom of the pot it will be the number given to that shape of pot, or the style of decoration, for use in the factory or workshop.
Probably just a code used in the factory for that shape/pattern
Pinch pots are simply clay which is pinched into shape, rather than being made on a wheel or constructed from coils. So all you need is clay, access to a pottery kiln for firming it, and glaze. Clay is all you need for a pinch pot. All you do is rool the clay flat but a little thick and shape a bowl type pot and pinch it thats it I've made one.
Some people make pottery for a living. They make bowls, plates and dishes and sell them. Other people like to make pottery because it is a fun and messy activity. It may appear to be easy, but it can be very hard to get a good shape out of the clay. It is a challenge, which is part of what makes it so enjoyable. It also makes great gifts and allows your creativity to run wild!
Ovoid
The word you want is Ovoid
Oval/ovoid
No an egg is not a sphere. It is an ovoid. This shape is named after the shape of an egg.
An egg-shaped, three-dimensional shape is an ovoid.
Ellipsoid, Ovoid, Prolate Spheroid, Spheroid
Both are ovoid\ kidney shaped- not circlular. Although the ovaries are larger.
I was thinking about that myself, recently. The answer is "egg shaped". Mathematically, it's an "ovoid". Eggs vary in shape and there is no exact "formula" for the shape of an egg.
A two dimensional figure would be an oval or ellipse. A three dimensional shape could be called an ovoid.
An oval is two-dimensional. An ovoid is a three-dimensional shape based on an oval - like an egg,
It's an ovoid, not an ellipsoid as some may think.
a 3d oval is called an ovoid and it looks like a type of egg