I found this stone on the bank of the Fraser River in southern BC and wonder what type of rock it is? I've never seen one like it before. Can you help me? Thank you 😀enter image description hereenter image description here

  • $\begingroup$ Oh wow. This looks like a basalt with enormous phenocrysts of plagioclase. Pretty rock! Unless there is an obvious fossil that looks like that, but I doubt it. $\endgroup$ – Gimelist Sep 9 '17 at 7:15
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    $\begingroup$ Thank you Michael. I will look more into it now that I have an idea of what type of rock it is. Cheers $\endgroup$ – Alexandra Fontaine Sep 9 '17 at 15:06
  • $\begingroup$ This should be converted into an answer and accepted. $\endgroup$ – AtmosphericPrisonEscape Sep 9 '17 at 16:00
  • $\begingroup$ I agree with Michael it is very likely a basalt porphyry. The image in from this site shows a similar rock with a freshly fractured surface, csmgeo.csm.jmu.edu/geollab/Fichter/IgnRx/BasPor-1A1.html. We have similar rocks with various amounts of porphyritic crystal clustering in basalt on Vancouver Island from the Karmutsen formation. $\endgroup$ – Friddy Sep 13 '17 at 19:03

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