The phrase "as immutable" is correct and usable in written English.
It can be used to describe something that is unchanging or unable to be altered.
Example: "The laws of physics are often considered as immutable, governing the universe without exception."
Alternatives: "as unchangeable" or "as fixed".
But diamonds are not as immutable as the speed of light, notes Dr Cohen.
But isn't it modern practice to retire at the usual age, or is a constitutional monarch as immutable as the pope?
"The laws of prose writing are as immutable as those of flight, of mathematics, of physics," Ernest Hemingway wrote to Maxwell Perkins, in 1945.
What's alarming is her unyielding belief in honour and vengeance, her faith in a code that's as immutable as the landscape itself.
Her character, once created, was as immutable as Jean Harlow's at MGM; the press didn't want to hear positive information that would contradict it.
For Mr. Hanson, exploitation of the market is natural law, as immutable as death and delays on the Brooklyn Queens Expressway.
And the canyons, arches, spires and sandstone monuments are as immutable as ever in their demonstration of the slow clock of geologic time.
Our hard, clear, fierce winter cold felt as immutable as the peaks of the Alaska Range towering in the distance, across the Tanana Flats.
And he thus disproved an axiom of photography that had seemed as immutable as the laws of physics: when buying a lens for a D.S.L.R. camera, "low cost" and "ultra-wide aperture" are mutually exclusive terms.
The prime Fifth Avenue shopping district — stretching from Rockefeller Center on 49th Street up to the Plaza Hotel on 60th Street — might seem almost as immutable as the faces on Mount Rushmore.
But are these forms as immutable as some distinguished naturalists maintain; or do not our domestic animals and our cultivated or artificial plants prove the contrary?
