Something Old, Something New, Something Borrowed, Something Blue?

Question

It might be the product of a fertile intellect,
Something fresh, never seen by cognoscenti nor hoi polloi.
It might be something long forgotten, lost in some abandoned storeroom,
To be rediscovered some day, in a pile of dusty tomes or mouldering manuscripts, maybe?

It might be a thing you find quite intriguing,
Something a friend might have, but let you use also.
It might be something that captivates with salacious appeal,
To pull you back to it, again and again, right up to the very end?

If made a bit longer it's made a lot shorter.
Sometimes tangible, sometimes just an idea.
If made quite explicit it will be quite a bit sketchier.
The future may bring it a friend, or a few, or many — or none?

Nerves steeled, it might be blue as lapis lazuli.
Once aware, you may want to check it out for yourself, I guess.
In the United States, it might be great — but please harbor no illusion,
That may be the truth indeed, but it is much more likely to be merely ironic jest.

So, what is it?

Answer 1

I have an idea it is a

novel

It might be the product of a fertile intellect, Something fresh, never seen by cognoscenti nor hoi polloi.

Novel as an adjective means new or unusual, from Latin novus (new).

It might be something long forgotten, lost in some abandoned storeroom, To be rediscovered some day, in a pile of dusty tomes or mouldering manuscripts, maybe?

It might be a literary book, unknown to the world, such as Harper Lee's Go Set a Watchman.

It might be a thing you find quite intriguing, Something a friend might have, but let you use also.

An interesting book, maybe enjoyed by a friend and passed to you to read.

It might be something that captivates with salacious appeal, To pull you back to it, again and again, right up to the very end?

It could be a thriller or a real page-turner which you feel impelled to find out the ending.

If made a bit longer it's made a lot shorter.

A novella is a shorter form of a novel.

Sometimes tangible, sometimes just an idea.

A novel may be a book (noun) or an idea (adjective).

If made quite explicit it will be quite a bit sketchier.

Explicit clues graphic novels which have much drawn art - thanks OP for this and some further...

The future may bring it a friend, or a few, or many — or none?

Books may have sequels such as the Harry Potter series.

Nerves steeled, it might be blue as lapis lazuli. Once aware, you may want to check it out for yourself, I guess.

Danielle Steel is the best-selling living author, writes suspense and romance - can be blue.

In the United States, it might be great — but please harbor no illusion, That may be the truth indeed, but it is much more likely to be merely ironic jest.

The term Great American novel refers to one which embodies the truth about an important aspect of the American way of life and is exceptionally well written. These may be Moby Dick, The Catcher in the Rye, Roots, or Catch-22 which is tremendous and ironic.
In general some publishers may proclaim the next great American novel.

The Title: Something Old, Something New, Something Borrowed, Something Blue?

The novel originated centuries ago, is popular today, borrowed from libraries and can be erotic!

Answer 2

Bonus mini puzzle (hidden in the riddle):

The steganography tag would be appropriate here, but this is unrelated to the main riddle.

Looking at the structure of the riddle, you'll see

that the first and last letter of each line per paragraph give the following pattern:
ISIT TIME?
ISIT GOLD?
ISIT RARE?
NOIT ISNT

Or

Is it time? Is it gold? Is it rare? No it isn't.