Particular slow-growing cactus, characterized by solitary but also tufted habit. From its white areoles sprout tiny clear, flattened spines and, during the summer, it generates amazing white flowers, usually in clusters. Its stem, with a globular shape and rather depressed at the apex with slightly rounded ribs, has typically a grayish-brown color but, in the specific case of the variegated version, it shows yellowish patches due to the lack of chlorophyll. These spots are chromatic anomalies much sought after by enthusiasts, who never miss a chance to grab rare pieces.