@Drifa does indeed have the correct answer.
'
I am light of brightness', referred to it reputedly holding the light of the sun within it. '
Young of year' was a bit of a naughty clue from me, because it not only refers to having originally been made (maybe) in the first age, but also refers to how the Elessar/Elfstone was able to make all that had grown aged and withered look young again.
'I am pastures, forests, gardens fair.' .. well all those things are green, and the gem of the Elessar/Elfstone was of course green. But also, this refers to where Galadriel had been looking to have 'trees and grass about me that do not die'.
'I am winged and have twice took flight' .. because the gem is set in an eagle-shape of jewellery, so the eagle has wings. The 'flight' here is not literal, but figurative, because Idril fled from Gondolin whilst wearing the Elessar, and Earendil later took it with him on his desperate journey from Middle Earth to plead help of the Valar. So '
upon my wings none do i bear.'
'I
am two in twain and not the same' .. yes, this is because the history of the Elessar in canon split into two different versions.
'
Ruler of the skies', Because the Eagles are considered by many to be the kings of the sky/of birds, as opposed to say the lion which is king of the animals in popular culture. And
'ever for she' refers to Galadriel, because in both of the two contrasting tales of the Elessar, they are given to her.
'
There are more than one bequeathed my name' .. Aragorn Elessar uses the name of the Elessar Elfstone, which is his birthright.
'I passed hand to hand, and came to me.' .. so this part refers to the Elessar gem coming through the hands of people who had it in their possession through the years (whichever version you want to look at) and came at last to be owned by a man who is actually named 'Elessar'.
Thankyou all of those who took the time to guess, and I'm sorry it was such a nightmare.
@Drifa, the floor is yours.
