In the years since the Massachusetts Quilt Documentation Project got underway in 1994, it has examined 6,000 quilts preserved in museums and historical societies and treasured in private homes. They are, as historian Marla R. Miller notes, “artifacts of sentiment . . . mediums for nostalgia, affection, and veneration across generations.” And they are also, she writes, “texts of historical insight.” Some 200 examples are now handsomely displayed in “Massachusetts Quilts: Our Common Wealth,” edited by Lynne Zacek Bassett, the project’s founder. The book offers commentary on each quilt, its design and composition, the particular circumstances surrounding its making, and, frequently, the maker herself. In all, it is a valuable document of the Commonwealth’s cultural history.