This is a quite a classy Sedum - it comes away from a central crown in spring and the foliage is dark from the start. It flowers freely later in summer - large golden heads carried on plants with very dark, shiny, reddish foliage, much nicer than this photograph suggests. It's a lovely contrast. About 15cm (6") at most and dies back to resting buds for winter.
Easy in a sunny site with well-drained soil and a good choose for trough or container growing - it's very neat in its growth. One of my favourite Sedums.