This is Lynda's photo of the slope of SP Crater. It is steeper than it looks, and very difficult to climb because the cinders spill down the slope as you try to ascend. Larry was good at finding beautiful rust-red volcanic bombs. Lava hardens into basalt and related rocks. The most abundant gases erupted are water, carbon dioxide and sulfur gases.
Dust is the finest.
Sand-sized particles may be called ash. Lapilli are pea-sized and cinders are golf ball sized. Anything bigger is called a bomb. This is another captivating Larry Chandler photo. It is a bunch-grass in the middle of the SP Crater lava flow.