This picture of Sunderland choristers was discovered inside a book donated to the store – and the workers were keen to identify the singers.
Scores of people contacted the Echo following the picture's publication last month, with some putting more than a dozen names to the faces.
But for one lady, Dorothy Pickering, the photo brought back some extra special memories. Her father, Clifford Hartley, was the choirmaster.
"It shows members of Bishopwearmouth Church Choir, including my father, in 1951. It was taken to mark the Festival of Britain," she said.
"The choir was affiliated to the Royal School of Church Music and was invited to spend a day singing at the Festival Church in London.
"My father took a whole crowd of the choristers down to London by train. It was a very prestigious event and was even broadcast by the BBC."
Dorothy, who now lives in Middlesbroough, was 20 at the time of the concert and still remembers that long-ago Wednesday very clearly.
"It was my half-day off from Knightalls, the furniture shop, so I was able to listen to the concert on the radio," she said. "It was very, very good."
Halifax-born Clifford Hartley had arrived in Sunderland just a few years earlier, in 1946, after a distinguished war career in the RAF.
The talented organist took up the role of music master at Bede Grammar School, devoting much of his time to developing the school choir.
He also stepped in as organist and choirmaster at Bishopwearmouth Church – a task which inspired a new musical ambition for him.
Hartley decided that Sunderland needed to have a choir to be proud of, a choir which could perform the most ambitious choral pieces ever written.
Just a few weeks later, Bishopwearmouth Choral Society was born. That it still thrives to this day is testament to his enthusiasm.
Dorothy, who was a pupil at Bede and a member of her school choir at the time, still remembers her father first pulling the idea together.
"I recall him walking home with me one day and asking if I thought the girls in my choir would be interested in joining a choral society," she said.
"I told him that yes, I was sure they would, but only if he could get some men involved. So he offered to get the Bishopwearmouth men to join too.
"That was how it all started, really. Once our two groups had signed up, so lots more members joined up very quickly as well. It was wonderful."
Hartley took to the stage as the group's conductor, while Bede sixth former Dorothy Dodd volunteered as accompanist for the first season.
The first concert, Haydn's Creation featuring the famed soprano Isobel Baillie, was held just a few weeks later – to great acclaim.
"I was one of the original members, as I was already in the school choir, and I remember it being an exciting time," said Dorothy. "Music was always my father's life. He became a church organist at 16 and started choirs wherever he was posted during the war as well."
By the end of the 1948/9 season, the society had staged its first Messiah, as well as Elgar's The Light of Life and Mendelssohn's Elijah.
The choir was soon the toast of the town, just as Hartley had hoped for, and he remained the conductor, chairman and choirmaster until 1974.
"He was always devoted to his music and was made a life patron of the group in 1979," said Dorothy.
"My mother sometimes said that he put his music before his family.
"I don't agree – although we often used to tease him about it!"