There were, on the roof, the expected things:

cigarette lighters

glass

cast off from the adjacent apartments

but the longer we stood on the gravel the stranger were the items that appeared 

Necklaces and perfume bottles,

decayed

scissors from a shipwreck or an excavation

not one but two sets of nail clippers

a chewed on pencil

the metal reddened, the wood and plastic whitened, the forms distorted

but even the faded colors of the lost toys bright against the tarry gravel.