The phrase "a keystone for" is correct and usable in written English.
It can be used to describe something that is essential or foundational to a particular system, idea, or structure.
Example: "Education serves as a keystone for personal development and societal progress."
Alternatives: "a cornerstone of" or "a foundation for".
Accurate company accounts are a keystone for any proper capital market, not least America's.
Such a mega-structure would become a keystone for regional co-operation.It will almost certainly never be built.
It's a keystone for the entire project, a woman embracing a history of pain and transforming it into freedom.
The chorus forms a keystone for the whole album: "A nuclear error, but I have no fear / London is drowning and I, I live by the river".
It is widely seen as a keystone for peace.Marcos, a media junkie, greeted the new government, inevitably, with a press conference the day after the inauguration.
"I thought, that looks like a keystone for an archway," he said, then fresh from four months of studying architecture and archeology in Rome.
When she played Mrs. Pynchon, the publisher of The Los Angeles Tribune on "Lou Grant," the role became a keystone of her career; for it she won four Emmy awards.
"It really is the basis for a keystone of our effort to keep the faculty intellectually alive and hire and retain qualified people," Dr. McGill said.
[In a Keystone Poll for Franklin and Marshall College released on Aug. 17, 35percentt of voters strongly agreed with the statement that Mr. Bush "shows strong leadership qualities," with 24percentt saying that about Mr. Kerry.
It also teaches schoolchildren about the history of the huarango in Peruvian culture and its significance as a keystone species for the desert, its roots fixing nitrogen in poor soil and its leaves and pods providing organic material as forage.
Scientists say salmon are a keystone species for the region.
