In The Lord of the Rings, Aragorn wears a jewel called the Elendilmir, or Star of Elendil, upon his brow. This stone, which was also known as the Star of the Dunedain and the Star of the North, was later presented to Samwise Gamgee by Aragorn Elessar.
In Unfinished Tales, in the chapter The Disaster of the Gladden Fields, we learn that this was the second jewel to bear this name, and that the first one was lost with Isildur when he died; this first Elendilmir was later found by Aragorn Elessar and Gimli in Orthanc, and Aragorn kept it, wearing it only on special occasions.
In the footnotes to the chapter, things become even more confusing. There it is said that the Elendilmir worn by Isildur was actually the second incarnation of the Elendilmir.
The first was actually created for Silmarien in Numenor. The second was created by King Tal-Aldarion for his wife Erendis, also in Numenor, and this was the one that ended up being lost with Isildur. The third incarnation of the Elendilmir was created by the Elves of Imladris for Isildur's son Valandil, and was then passed down through the line of the Dunedain, eventually coming into the hands of Aragorn.
Finally, Christopher Tolkien makes things even worse by suggesting that the Elendilmir which Aragorn gave to Samwise was a totally different jewel, meaning that it is actually the fourth incarnation of the Elendilmir.
I can't imagine that J.R.R. Tolkien intended for this issue to be so ridiculously complex and impossible to understand.
Is there any way to determine how many Elendilmirs there were, and what happened to each of them? Furthermore, is there any reason to believe that J.R.R. Tolkien meant for us to think that the jewel given to Samwise Gamgee was anything other than the Elendilmir which Aragorn wore before finding the lost Elendilmir of Isildur?