2C-B in aqueous, 10% hydrochloric acid, or 10% acetic acid solutions forms long yellow needles and clusters of short needles. The long needles appear either individually or in loose clusters whereas the short needles appear as tight sheaves or clusters. The tighter the cluster, the darker the growth appears. Both forms of crystals may be observed simultaneously. The darker clusters appear very bright under crossed polars and the individual needles are very faint.