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Abstract-We report physical properties (bulk and grain density, magnetic susceptibility, and porosity) measured using nondestructive and noncontaminating methods for 195 stones from 63 carbonaceous chondrites. Grain densities over the whole population average 3.44 g cm )3 , ranging from 2.42 g cm )3 (CI1 Orgueil) to 5.66 g cm )3 (CB Bencubbin). Magnetic susceptibilities (in log units of 10 )9 m 3 kg )1 ) averaged log v = 4.22, ranging from 3.23 (CV3 Axtell) to 5.79 (CB Bencubbin). Porosities averaged 17%, ranging from 0 (for a number of meteorites) to 41% (for one stone of the CO Ornans). Notably, we found significant differences in porosity between the oxidized and reduced CV subgroups, with the porosities of CV o averaging approximately 20% and CV r porosities approximately 4%. Overall, porosities of carbonaceous chondrite falls trend with petrographic type, from type 1 (CI) near 35%, type 2 (CM, CR) averaging 23%, type 3 (CV, CO) 21%, to type 4 (CK and some CO) averaging 15%. There is also a significant decrease in porosity between meteorites of shock stage S1 and those of S2, indicative of shock compression.

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[1] Accurate lunar rock densities are necessary for constructing gravity models of the Moon's crust and lithosphere. Most Apollo-era density measurements have errors of 2-5% or more and few include porosity measurements. We report new density and porosity measurements using the bead method and helium pycnometry for 6 Apollo samples and 7 lunar meteorites, with typical grain density uncertainties of 10-30 kg m À3 (0.3-0.9%) and porosity uncertainties of 1-3%. Comparison between igneous grain densities and normative mineral densities show that these uncertainties are realistic and that the helium fully penetrates the pore space. Basalt grain densities are a strong function of composition, varying over at least 3270 kg m À3(high aluminum basalt) to 3460 kg m À3 (high titanium basalt). Feldspathic highland crust has a bulk density of 2200-2600 kg m À3 and porosity of 10-20%. Impact basin ejecta has a bulk density of 2350-2600 kg m À3 and porosity of $20%.