These often look like a combination of rectangular and cylindrical bottles.
Then there are the oddball shapes, which tend to be more sought-after, including 'teapot,' 'umbrella,' and 'turtle' (it really does look like a turtle! Though many ink bottles are made of glass, not all are.
It would be natural to assume that ink bottles date to the beginning of glassblowing and the written word, but prior to the 18th century, the most common form of ink was a cake or powder, which the writer would mix with water.
Black metal screw on lid shows some rust on the edges, excellent label and box.
I1638 $15 Weber Drawing Ink Bottle - This vintage 1920s bottle has one of the most elegant labels I've seen.
The most valuable colors are unusual ones like yellow and purple, while colors like aqua and clear are more common.
Embossed bottles or ones with intact labels also increase an ink bottle’s value, adding aesthetic appeal as well as important information about the bottle's origin. Stoddard New Hampshire Produced Pontiled Master Ink Bottle Crude And Whittled!! Rare Civil War Relics Blown Open Pontil 12 Sided Glass Inkwell Ink Bottle Open Pontiled 8 Sided Green Umbrella Ink Blue Green Cone Ink #2 With "x" On Base Lyndeborough Nh Glassworks??
Many makers had their own distinct stamp or scar on their bottles.