accumulated accumulations aged calcium-carbonate candle-shapes caves ceilings coloring colors colouring colours columns crystallisation crystallise crystallization crystallize deposits distinctive edge edges floors formation forms icicle-like minerals old Particles pillars pointed shape shaped shapes Singapore slow slow-growth slowly smooth Stalactite stalactites stalagmites subterranean surface surfaces texture textures unusual white Australian banksia-attenuata Banksia-tree bristly brush-like color colour curly flora flower furry golden green large leaves native saw-edged-leaves serrated serrated-leaves soft spring thin trees yellow brown cone seed-pod age birth birthday cake candle candles celebrate celebration decorated decoration decorations dessert drawing festive fire five food frosting party appearance birthday cake black bright red cakes colored colorful coloured colourful cupcakes finger food fun food iced icing party food party snacks red snacks sticky sweet sweets