Page 2

page 1 | page 3 | page 4


096
097
098
099
100
101
102
103
104
105
106
107
108
109
110
111
112
113

114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
still more

page 1 | page 3 | page 4

Some considerations:   Most (~99%) meteorites found by amateurs are ordinary chondrites, irons, and stony irons because (1) these are the most common kinds of meteorites that fall from the sky and (2) such meteorites are often easy to spot because they look different from “ordinary” rocks, even to an amateur.  For example, most chondrites and all irons and stony irons contain iron metal and are, therefore, magnetic in that they will attract a compass needle.  They are also a bit denser (heavier for their size) than most terrestrial (Earth) rocks. 

About 3% of stony meteorites are achondrites such as howardites, eucrites, diogenites, aubrites, ureilites, lunar meteorites, and martian meteorites. Most achondrites contain little or no metal (<1%) and are not magnetic. All strongly resemble Earth rocks.  Put another way, many kinds of Earth rocks “look like” the rarest meteorites.  If an achondrite does not have a fusion crust (because it’s worn off or it’s a piece from the interior of a large meteorite), it is impossible to recognize it as a meteorite without doing expensive and time-consuming chemical, isotopic, and mineralogical analyses.  All the martian meteorites, for example, are rock types that are common on Earth (basalts, peridotites, pyroxenites, dunites).

Many of the people who have sent us rocks and photos have done so because of our web site on lunar meteorites.  Thus, many of the photos in the collection above really don’t look anything like “normal” meteorites.  A few resemble lunar meteorites.  Again, however, many terrestrial rocks, particularly sedimentary rocks and some volcaniclastic rocks, superficially “look like” the brecciated lunar meteorites.  Your chance of finding a real meteorite is very low. For example, there have been only about 23found in Missouri and 9 found in Illinois in the past 200 years. Less than 1 in 1000 of all known meteorites are from the Moon (same for Mars).  Thus, your chance of finding a rare type of meteorite is extremely low.

The bottom line is that if you have a rock that has no fusion crust and it looks like a terrestrial rock, then it is almost certainly not a meteorite. Meteorite dealers and scientists aren’t going to be interested in examining, studying, or analyzing it.

 

See also: Some Meteorite Realities
  

Many thanks to Bob Osburn, Karla Kuebler, Ryan Zeigler, Bob Dymek, and Brad Jolliff
for examining or analyzing many of the the rocks and photos depicted here.


www.catchafallingstar.com
www.catchafallingstar.com

This web site has been featured in the following media

Yahoo! Picks - 3 November 2005
Science NetWatch- 9 December 2005
Washington University News & Information - February 2, 2006
Popular Science FYI, April, 2006 (p. 90)


Prepared by:

Randy L. Korotev


Department of Earth and Planetary Sciences
Washington University in St. Louis


Please don't contact me about the meteorite you think you’ve found until you read this and this.

e-mailkorotev@wustl.edu

Last revised02-Sep-2011