Fig. 2.  Carbonate compositions in A84. a. 6,736 semi-quantitative analyses from two individual carbonate regions in ALH 84001. b. 700°C ternary phase diagram from Anovitz and Essene (1987). Quantitative analyses are shown as black circles, shaded area shows compositions seen in a. Black arrows show representative core-rim zoning trends within individual rosettes in the two regions; Grey arrows show broad reversal of Ca at intermediate compositions (c) and narrow reversal of Fe-Mg in rims (d).