true, though I often say no, before I change my mind
atm, no, I would not carry a 3/4 pound copper 18650 light, but Im a slender guy that wears no duty belt
for others, this might be awesome!:
here is another popular copper 18350 light

it weighs 1/2 as much as the one in the video
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both those lights use the same electronic ramping UI, Anduril… it has tons of great features and will keep anyone entertained for days, playing with the options… 
things like this

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regarding ketchup, it definitely cleans copper, but it also pits it, and the result is not as shiny as polishing.
I like to use Sunshine cloth when I want to remove patina
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I recall being worried about the smell of copper, then I learned copper kills germs and decided the smell was not a bad thing…
some info and links about copper’s antibacterial properties (fancy word of the day… Olygodynamic)
After I learned that the USA settlers traveling West in covered wagons, used silver and copper coins in their water barrels, to prevent algae, I started keeping a USA Silver Walking Liberty 50cent piece in a clear Nalgene bottle filled with water.
The Nalgene bottle with silver coin, has been sitting in my Van, parked in full sun, for over 6months, and has not developed any algae, nor funky smell.
The US Silver coins are 90% silver, 10% copper. Both are antibacterial and not harmful to humans.
Quote:
Originally Posted by jon_slider View Post
https://www.antimicrobialcopper.org/us/mrsa
“many copper alloys can legally claim a 99.9% kill of MRSA within two hours”
In India it was traditional for people to collect and store drinking water from rivers and streams, in Copper pots. When they switched to plastic water jugs, cases of infant dysentery and death went up. A study was done that added coils of copper wire to the plastic water jugs, and the dysentery rate, and infant mortality fell.
Boiling water also kills bacteria, but in poor third world countries, the fuel used for cooking, often charcoal, is very expensive, so drinking water tends not to get boiled first.
http://www.rosincerate.com/2015/11/killing-microbes-with-copper-and-silver.html
“It’s long been recognized that storing water in a copper or silver vessel makes it safer to drink. The Smith Papyrus, an ancient Egyptian medical text, mentions using copper to disinfect drinking water. Alexander the Great brought along silver containers for storing water during his efforts to conquer the world. Old Ayurvedic medical texts advise keeping water in copper or silver pots. The Aztecs, ancient Greeks, and Romans were also into this disinfection approach. American pioneers making their way west during the late 19th century dropped copper or silver coins in their water barrels to slow the growth of microbes during their travels. During WWII, Japanese soldiers did something similar, placing copper pieces in their water bottles to try and avoid dysentery.”