PHILADELHPIA —They were a collective of Philadelphia writers — teachers, students, newcomers to Black literary circles, others well-acquainted with rising stars from Harlem’s artistic milieu. They decided to put out a literary journal themselves. They’d call it Black Opals. Black Opals ran between 1927 and 1928, at a time when the Harlem Renaissance was in full swing. The name came from the poem “Longings,” by one of their founders, writer and educator Nellie Rathbone Bright. “I want to feel the rain on my cheek,” Bright wrote, in the poem’s last five lines, published on the first page of the …