Manuscript & Correspondence Archive

University of California, Los Angeles UCLA

Institute for Geophysics and Planetary Physics
Los Angeles, California 90024-1567
FAX: (310) 206 3051

28 December 1994

Mr. O. Richard Norton
Central Oregon Community College
Department of Science and Mathematics
Bend, OR 97701

Dear Mr. Norton:

I have just finished reading Rocks from Space and I wanted to let you know how much I enjoyed the book. I've already recommended it to several meteorite researchers. I found the text informative and lively and was pleased by the large number of quality illustrations. I was disappointed that Tim McCoy's review of your book in Meteoritics was not more positive.

There are some minor errors, however, and I point them out to you in the spirit of constructive criticism, so that if you ever publish a second edition, these can be corrected.

(1) Jeff Grossman pointed out that your dedication is a little ambiguous and could be interpreted to mean that hunters are pursuing the scientists who study meteorites. Personally, I find this frightening.

(2) Most of the problems deal with classification and mineralogy. For example, on p. 177, orthoclase is rare but not absent in meteorites--it occurs in some ordinary chondrite regolith breccias where it formed by shock processes; pyroxenes also occur in rare iron meteorites (e.g., Steinbach); olivine occurs in mesosiderites also; amphibole occurs as a rare phase in enstatite chondrites (however, instead of OH we find F); troilite also occurs abondantly in chondrites; magnetite occurs as small grains in many LL chondrites.

(3) P. 178; the ternary diagram is labeled molecular % Fe₂SiO₄, but instead shows molecular % forsterite.

(4) p. 182; "Chondrites are often called 'ordinary chondrites'" -- Of course, only ordinary chondrites (H,L,LL) are called ordinary chondrites; carbonaceous and enstatite chondrites are never called ordinary chondrites.

(5) Chemical classification of chondrites P. 186 and following:
Enstatite chondrites comprise two groups EH and EL which are derived from two separate parent bodies; this is exactly analogous to ordinary chondrites comprising three groups. One cannot list H, L, LL and E. There are also two additional established groups of carbonaceous chondrites CR (Renazzo-type) and CK (Karoonda-type) as well as grouplets (e.g., Coolidge-Loongana 001) and unique carbonaceous chondrites (e.g., LEW85332; Adelaide). Within the last year or so, a fourth class of chondrite has been established: the Rumuruti or R chondrites: these are not ordinary, carbonaceous or enstatite chondrites. The chart on p. 187 does not list any type-3 enstatite chondrites; this is incorrect -- there are more type-3 enstatite chondrites than type-4. There are both EH3 and EL3 chondrites. Also, there are no CV4 or CV5 chondrites -- these meteorites have all been placed in the CK group. There are no CO4 chondrites -- the sole one was Coolidge, now a member of its own grouplet. Also no meteoriticists use the term "olivine-bronzite", "olivine-hypersthene" or "amphoterite" chondrites anymore. These terms will not appear in the next edition of the British Museum Catalogue. On p. 193, you state that type-2 has only one group member, CM. This is incorrect: the CR chondrites are all type 2. On p. 194 you state that there are CV2-5 meteorites. All CVs are type 3. The sole type 2 was Al Rais in McSween's 1977 paper, but this is now considered an anomalous member of the CR group. Also, as I said earlier, the type 4-5 CVs are now part of the CK group. On p. 203 you state that only one angrite is known. Two others were recovered from Lewis Cliff in Antarctica in the 1980s. Also on p. 203 (and earlier), no one uses these designations anymore: Keil used them in the 1960s and unfortunately reprinted them in his book in 1980 or so. Also, it is silly to give the same designation of eucrite (EUC) to shergottites when no one calls the latter group eucrites and they probably come from Mars, unlike the eucrites. P. 230, schreibersite and cohenite do occur on Earth; they are very rare and occur only in terrestrial native iron. Both also occur in chondrites. Not everyone considers all irons from cores: The three non-magnetic groups (IAB, IIICD, IIE) have planetary gases and may be from pools of metal at the floors of impact craters on chondritic asteroids. P. 235, no one uses the term siderophyre anymore. Besides, Steinbach isn't alone anymore: Sao Joao appears to be very similar. P. 237; Mesosiderites probably formed in a very different way than pallasites -- the most probable model is detailed in Icarus 101, 201-212 (1993) in a paper written by Rubin and Mittlefehldt. I've also written this up for Scientific American, but they are still sitting on it.