Maybe one can't argue for efficiency in this case, but glass carafes (especially this one, with its ever-elegant natural water filter) evoke a sense of calm and point directly to thoughtful, intentional design. Simply looking at this piece that embodies form and function makes us breathe a little more deeply.
This hand-made, mouth-blown glass carafe from Mjölk comes with a piece of water-filtering coal (white coal, or Kishu Binchotan, which is made by heating a piece of Japanese oak in a kiln), which soaks up chlorine from tap water and filters good minerals into the drinking water.
Find it: Glass carafe & Kishu Binchotan (coal) at Mjölk, $125
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How about a little more about the functionality. Does the charcoal float to the hole when you pour this? Does it shed dirt in the water or is it solid enough to not release any of the blackened wood. How long does it take to filter out the chlorine? This seems more like an aesthetic piece than a functional one. If it were as easy as good quality charcoal in a water bottle wouldn't we all be using it already? Burnt wood and glass is cheap. This is not.
So this is a $125 glass bottle with a hunk of burnt wood inside? Um, how do I get in on this market?