Nanjun, they are great for cutting blocks. Take them out and use them. In a joint venture a friend and recently made a frayed block denim and cotton quilt for an 80th birthday gift. She was using a very small pair of scissors to cut the seam sapaces to fray, because they were sharp. I was cutting in another are with a pair of these and did almost three times as much as she did in the same time period. Mine have remained very sharp. I love them. Try yours.