Fig. 3From: Assessment of the potential respiratory hazard of volcanic ash from future Icelandic eruptions: a study of archived basaltic to rhyolitic ash samplesBulk compositions of volcanic ash samples. Sample compositions are plotted according to magma type as total alkali (K2O + Na2O) versus silica (SiO2). Data for Snæfellsjökull sample (Snae-1) from Martin and Sigmarsson [77]Back to article page