is this a rust stain that’s just been baking in the sun for a few years or something else? The pavers are transplanted from the neighbors half of the top floor. Never seen a pink stain like this before. Thanks in advance. I really appreciate any opinions.
Look like fertilizer stains
That’s what I’m leaning towards due to the droplet pattern and the color. They have a fire pit that has some discoloration around it that’s very light but it gets hot up there and Ive never thought about if rust stains would fade from the UV. Hydrofluoric acid is what I hear works but I’m trying to go the gentlest route possible because what water doesn’t drain between those pavers will has 9 floors of neighbors and the building itself to pass before it hits the ground.
