The phrase "an essential cornerstone of" is correct and usable in written English.
It can be used to emphasize the fundamental importance of a particular element or concept within a larger context.
Example: "Education is an essential cornerstone of a thriving society, as it fosters critical thinking and innovation."
Alternatives: "a fundamental basis of" or "a key pillar of".
In randomised controlled trials (RCTs), patient informed consent documents are an essential cornerstone of the study flow.
Just a few months ago, a report commissioned by the New York New Media Association, a trade association, said that interactive cyberbusinesses employed more than 100,000 people in the city and were "rapidly challenging many other traditional New York industry sectors as an essential cornerstone of the growth of the regional economy".
His theories form an essential cornerstone of what physicists call the Standard Model, which explains in a unified way three of the four fundamental forces of nature: strong, weak and electromagnetic.
Guaranteeing that parole is not merely a revolving door for those released from the system is an essential cornerstone of any de-incarceration plan.
Both India and Pakistan have made control of a unified Kashmir an essential cornerstone of their national identities and have fought several wars between 1947 and 2002 on this issue.
Calling the campaign "The Children's Challenge," the members of GAVI argued that children have a right to good health and that protecting the world's children against preventable diseases was not only a moral imperative, but an essential cornerstone of a healthy, stable world society.
Ultimately, if advertising is a game of scale, then Facebook's user numbers and the engagement of those users will be an essential cornerstone in trying to gauge the company's future success.
Perhaps most important, Mr. Bloomberg seems committed to Mr. Giuliani's signature issue, the fight against crime -- an indication that the new mayor recognizes that public safety is the essential cornerstone of a flourishing city.
SpaceTime is an interesting acquisition not only because will help Nokia tap into utilising more artificial intelligence — which by many accounts has become and will be the essential cornerstone of how IT services operate — but because it's also bringing something else to the business: customers.
These findings confirm, for the time being, trastuzumab remains the essential cornerstone of any routine treatment strategy in HER2-positive breast cancer.
