Not only is this strange stuff rare, but it is very expensive to make. This article from Listverse will tell you more than I could, that's a fact!
What Is Fogbank?
When the US Navy set out to refurbish their W76 warheads, a significant part of their nuclear arsenal, they ran into a serious problem. Once they opened up the warheads, they discovered a classified material code-named “Fogbank” that needed to be replaced. Except that no one knew how to make it.
Fogbank was made in the 1970s and ’80s, and there were very few records detailing its creation. Anyone involved with it had already left the agency. This led to a $23 million attempt to create a replacement material, which ultimately failed. Another $69 million was spent to rediscover Fogbank’s manufacturing process, which was successful.
Although Fogbank is critical enough for the Navy to invest $92 million of taxpayer money to recreate it, no one except those involved in the project knows exactly what it is. A former manager in its development went on record as saying that its composition, use in the weapon, and method of creation are all classified. Experts suspect that it’s a kind of aerogel that functions as an “interstage” in the warhead, surrounding the fission and fusion parts of the bomb and transferring energy between them. Whatever it is, it’s a reminder that even the most critical pieces of technology can fall victim to the “fog” of time.
Call me crazy, but I suggest the folks making this stuff take some detailed notes on the recipe this time around. Don't want to hear someone say "I haven't the foggiest" when asked how to make some more, ya know?
Coffee out on the patio this morning. Summer is back to stay, I reckon.