NWA 1694

CK3
standby for northwest africa 1694 photo
Found October 2002
no coordinates recorded A single fusion-crusted stone weighing 47.1 g was found in the Sahara Desert and was subsequently purchased in Safsaf, Morocco by American collectors. Classification was conducted at Northern Arizona University (T. Bunch and J. Wittke). This very fresh find (W0/1) is classified as an unshocked (S1) CK3. Northwest Africa 1694 is composed of 47 vol% fine-grained matrix, 44 vol% chondrules (up to 1.2 mm), 6 vol% sulfides (containing inclusions of chlorapatite and silica glass), 2 vol% Cr-rich magnetite, and 1 vol% CAIs. Although this meteorite is similar to NWA 772, the two are not considered to be paired.

After in-depth analyses of many CV and CK meteorites having a wide range of petrologic types was conducted by Wasson et al. (2013), they presented a reasoned argument for merging the CK and CV groups into a single unified group. The geochemical and petrological justification for such a reclassification of the CK chondrites, along with details of their proposed taxonomic scheme, can be found on the Dhofar 015 page. Subsequent studies have demonstrated a high likelihood for separate parent bodies. One such study conducted by Dunn et al. (2016) compared magnetite in a number of CK and CV chondrites. They presented geochemical, mineralogical, and petrographic evidence which is more consistent with separate CV and CK parent bodies. Another study conducted by Yin et al. (2017) utilized a coupled Δ17O vs. ε54Cr diagram to plot several CK and CV chondrites. Through this technique they demonstrated that these two meteorite groups derive from separate parent bodies. Details of these studies can also be found on the Dhofar 015 page.

Our collections contain less than 20 different meteorites representating unequilibrated CK material. The specimen shown above is a 2.2 g partial slice of CK3 NWA 1694, however, a subtype has not yet been ascertained.


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