Numbering more than 10,000 texts, Princeton University's collection of handwritten Islamic documents, books and letters is the largest in North America.
They date from the 8th and 9th centuries - soon after the faith was founded - to the fall of the Ottoman Empire in the early 1900s; most have gone unseen outside New Jersey for nearly a century.
Now the university is starting a four-year project to categorise the collection, and to digitise and post online about 200 of the most important works so that scholars around the world can study them.
Don Skemer, Princeton's curator of manuscripts, said: "Our collection really is a world resource. Every single subject you can imagine that you could find in a library, it's all there."
Rare Quran copies
Documents to be scanned include rare, ornamental 9th-century Qurans; interpretations of the Quran and Islamic law; and treatises on philosophy, science, art, magic and medicine, as well as poetry and history.
Lavishly illustrated in inks that remain vibrant and lustrous hundreds of years later, the books include drawings depicting ancient battles and conquests.
"You couldn't put a price on it. It's a collection that took over 100 years to put together"
Princeton's curator of manuscripts
A botanical manual from the 15th century includes drawings and descriptions of different types of leaves and plants.
There are even instructions on how to write a good letter.
The collection was amassed mostly by a Princeton University alumnus in the late 1800s and given to the university in 1942. Written in Arabic script in Persian, Turkish and other languages, the manuscripts are stored in secure, climate-controlled vaults.
Skemer said: "You couldn't put a price on it. It's a collection that took over 100 years to put together".
Yaser El-Menshawy, chairman of Majlis Ash-Shura of New Jersey, the state's council of mosques, said the material will help Muslim scholars - and ordinary Muslims - around the world to learn more about their heritage.
"One of the things that really makes life easier for Muslims is the availability of information on the web," El-Menshawy said.
"For instance, I have to give sermons, and lots of times, it's so much easier today than it was 10 years ago; you just go online and enter the topic you want to speak about, and there's so much there.
"I think there will be a lot of interest in this."
The texts to be reproduced online will be photographed by cameras that will not damage the delicate inks and papers.
"One of the things that really makes life easier for Muslims is the availability of information on the web"
chairman of Majlis Ash-Shura
Overhead digital cameras to be used for the project can photograph only about four or five pages an hour because of the large size of the files.
About 200 of the texts should be scanned within two years, and it should take another year and a half to two years to have them online.
The digitised texts will be made available with no strings attached.
Skemer said: "There are no copyright issues with these.There are no impediments at all. It's a common heritage, and they will be available to anyone to look at."