These sturdy black columns were made by pouring concrete into columnar forms. Though these ones are part of a building in Potrero Hill, it’s not hard to imagine them as supports for a modern-styled arbor or trellis in a garden needing some verticality. Or, similarly, in a small grouping as a sculpture; add water flowing up the center and tumbling down the sides for a fountain. Simple and supportive, but with a big statement.