It is found in limited outcrops, on the W – NW – N and NE slopes of the volcano, plus another one at the northern cliff of the caldera. It refers to a bed of fallout aphyric dacitic pumice with characteristic fine vesiculated angular lapilli, 2-3cm average diameter;

some ash is observed as well. It is worthy to note the presence of two pumice hues (light-gray and gray) as well as obsidian fragments. The thickness of such occurrences does not exceed two meters. The occurrence on the inner cliff of the caldera is laid over caldera debris; it presents marked layering and reverse grading due to sliding on the steep slopes. So far any deposit of this formation above post-caldera domes has not been detected.