element wt% spot 1 spot 2 spot 3 spot 4 avg. H* - - - - - O* - - - - - C* - - - - - Na 0.32 0.40 0.21 0.93 0.5 Mg 0.03 0.07 0.03 0.05 0.0 Al 3.83 4.74 3.37 4.82 4.2 Si 1.64 1.88 1.26 1.73 1.6 P 0.90 1.12 0.91 1.24 1.0 S 1.19 1.29 0.90 1.07 1.1 Cl 0.03 0.00 0.03 0.00 0.0 K 2.04 2.91 2.39 3.85 2.8 Ca 17.51 21.96 14.56 17.53 17.9 Ti 0.04 0.06 0.06 0.07 0.1 Mn 0.05 0.04 0.03 0.00 0.0 Fe 1.51 2.25 1.78 1.70 1.8 Sum 29.07 36.70 25.54 33.00 31.1 *not included in elemental analysis