Mason jar

Reader's Digest 6月号の記事 'We Found a FIX HELP, HACKS. & HOW TO' からの引用です。
If you have a fire pit in the backyard or a camping trip coming up soon, start saving wine corks in a Mason jar. Fill the remainder of the jar with just enough rubbing alcohol to submerge the corks, but leave enough space at the top of the jar for them to swell. In a few days, each cork will make an excellent upcycled firestarter.

"Mason jar" は大文字で始まっているので米国メーカーのブランド名のようですが、どんなジャーなのか辞書にでているものか調べました。
・Oxford English Dictionary: A wide-mouthed glass jar with an airtight screw top, used for preserving fruit and vegetables.: He used to have some Mason jars that had money up on the shelf.
・Collins Dictionary: an airtight glass jar for preserving food: Word origin: named after its US inventor, John L. Mason (1832–1902)
・Merriam-Webster's Online Dictionary: a widemouthed jar used especially for home canning: Place vinegar, honey, shallot, poppy seeds, mustard and olive oil in a mason jar, screw on the lid and shake vigorously to combine ingredients.

梅酒やピックルを作るのに使う広口のガラス瓶ですね。発明家の名前から付けられた名称ですが、最後に引用した辞書の例の様に小文字でも使われるようなので、既に一般語になっているのですね。