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The calcium abundance in flare plasmas is estimated using X-ray spectra fromthe Solar Maximum Mission Bent Crystal Spectrometer (BCS) during the decays of194 flares (GOES classifications from B6.4 to X13) occurring between 1980 and1989. Previous work by Sylwester et al. found that the abundance varied fromflare to flare. That analysis is improved on here using updated instrumentparameters and by including all calcium lines viewed by the BCS instead of onlythe resonance line, so greatly enhancing the photon count statistics. Theabundance variations are confirmed with the average abundance, $A({\rm Ca})$(expressed logarithmically with $A({\rm H}) = 12$), equal to $6.77 \pm 0.20$for 194 flares (141 of which are new in this study). This range corresponds tofactors of between 1.7 and 7.2 larger than the photospheric abundance and soour results are in line with a ``FIP" (first ionization potential) effectwhereby low-FIP elements like Ca (FIP = 6.11~eV) have enhanced coronalabundances. The Ca flare abundance is uncorrelated with solar activity indices,but weak correlations are suggested with GOES flare class and duration (larger$A({\rm Ca})$ for smaller and shorter flares). The ponderomotive force theoryof Laming explaining the FIP effect gives a range of parameters within whichour estimates of $A({\rm Ca})$ agree with the theory. However, this then givesrise to disagreements with previous estimates of the flare silicon and sulfurabundances, although those of argon and iron are in good agreement. Smalladjustments of the theory may thus be necessary.

New Solar Flare Calcium Abundances with no Surprises: Results from the SMM Bent Crystal Spectrometer