Data in this database are freely available under the request of citation of   this paper   and the  paper   in which the data were published.

Spurr (Gunsight)

origin	crater Peak on the south side of Mount Spurr volcano, across Cook Inlet, Alaska, USA, 125 km west of Anchorage. The particles are from the 17 September 1992 eruption and were collected 265 km east of the volcano
main constituents	57-78 wt% glass, plagioclase feldspar, opx, magnetite, amphibole, cpx
practical significance	interpretation of remote sensing data. Analogues of other planets' atmospheric dust, and dust in comets, asteroids, and circumstellar shells
particle size	measured size distributions Fraunhofer: reff=3.5 μm, veff=8.2
particle shape	irregular
refractive index	estimated to be in the range [1.48-1.56] + i[0.0018-0.02]
color	dark gray
scattering matrix	632.8 nm
article	Muñoz O,Volten H, Hovenier JW, Veihelmann B, van der Zande WJ, Waters LBFM, Rose WI. Scattering matrices of volcanic ash particles of Mount St. Helens, Redoubt, and Mount Spurr Volcanoes. Journal of Geophysical Research, vol. 109, D16201, 2004