Bay waters as they looked under threat of night.

A single chrome bolt and nut set held two vertical piece of blue metal together.

A typical California blue sky that was marred that afternoon by a few misplaced clouds.

A blue light mounted on the side of a building on Brannan Street was turned off that afternoon.

A fire plug found on Harrison Street had writing on its blue top. The writing said, "Safety 75 ©."

A blue background with a ladder printed on in was the background for a display window.

A dirty footprint was found on blue stained plywood outside a building that was being refurbished.

A deeply blue Christmas tree ornament was found in store window inside the Westfield Center mall.

The bay waters appeared a deep blue just after sunset while on a Bay Cruise.

Horizontal blue blinds found behind a store window.

Motorcycles parked behind Old Town in Sacramento appeared blue in the evening shade.

A metal column was painted blue after posters had been applied. Over time the posters began to peel.

While walking to photograph parks, a blue plastic sheet was found discarded in the grass alongside a road in San José, Costa Rica.

The walkway between the restaurant and the rooms was outside. A cleaning cart was parked at the end of the walk and was filled with cleaning tools. Among the tools was this blue plastic mop or brush.

Rain had puddled on the blue car's hood.

A blue colored eel swam past blue rocks in an aquarium in the basement of the new California Academy of Sciences.

Mission Creek extended past the houseboats. One the other side was a small boat launching dock. In the dirt below that dock was found a modest pile of small glass chunks.

Wet ice at a public ice rink in Justin Herman Plaza appeared blue in the late afternoon overcast light.

Water puddled on ice at a public ice rink in Justin Herman Plaza. In the afternoon light that puddle appeared blue.

The "Marin" was a Sausalito Ferry run by Golden Gate Transit. Its top passenger level was covered with Plexiglas-like skylights. The one nearest the forward-most starboard side was dramatically cracked and appeared blue.

One of the skylights on the "Marin" Sausalito Ferry was cracked in an interesting pattern reminiscent of polar ice seen from an airliner .