This is probably a Belgian product, or perhaps French. It appears to be from the 1720-40 period. Many people call any bottle that is not English a Dutch Onion. The glass factories in the Netherlands were unable to keep up with the demand for bottles.
Therefore the wine and liquor merchants in the Netherlands bought bottles from Belgium, France. Spain, probably Germany and Portugal and anywhere else they could get them. The earliest Dutch Onions are generally very light in color as their glass makers were using wood for fuel.
The introduction of coal fired furnaces with their higher temperatures ushered in the Black Glass Period. England gave monopolies to their glass makers, so you don't see a lot of British glass on the continent or elsewhere. This bottle has shoulders and a slightly flattened side. It is the transitional bottle between the globe shaped onion and the mid-eighteenth century mallet.
It is much rarer than the typical Dutch Onion. It has a great color as well, they stand out in a crowd of Onions. You can spot them immediately.It is a good solid piece of glass. The item "BLACK GLASS BELGIAN ONION BOTTLE c. 1720 40" is in sale since Saturday, August 1, 2020. This item is in the category "Collectibles\Bottles & Insulators\Bottles\Antique (Pre-1900)\Utility & Black Glass". The seller is "carlasboy" and is located in Tampa, Florida.
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