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Gemstones, Minerals & Fossils
Gemstones and Minerals
❓Your Mineral Identification Questions answered here
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<blockquote data-quote="mbasko" data-source="post: 669235" data-attributes="member: 4485"><p>All the weathered/broken down bits of basalt I've encountered are still dark grey to black internally. A lot do have a light colour thru to rust red brown exterior.</p><p>Examples:</p><p>Outside showing light colour to rusty red.</p><p>[ATTACH=full]10119[/ATTACH]</p><p>Internal</p><p>[ATTACH=full]10118[/ATTACH]</p><p></p><p>Basalts typically retain the dark grey/black due to the manganese & pyroxene, weathering or "rusting" from the outside.</p><p>The sample also appears not to be fine grained enough for basalt & high in silica content (quartz grains). Basalt is low in silica.</p><p>Hard to tell from a photo on phone & not a lot of info.</p><p></p><p>If it's grainy & friable (crumbly) when broken I'm sticking with my initial amatuer guess <img class="smilie smilie--emoji" loading="lazy" alt="😄" title="Grinning face with smiling eyes :smile:" src="https://cdn.jsdelivr.net/joypixels/assets/8.0/png/unicode/64/1f604.png" data-shortname=":smile:" /></p><p></p><p>Either way it's definitely iron mineral content giving it the red colour.</p></blockquote><p></p>
[QUOTE="mbasko, post: 669235, member: 4485"] All the weathered/broken down bits of basalt I've encountered are still dark grey to black internally. A lot do have a light colour thru to rust red brown exterior. Examples: Outside showing light colour to rusty red. [ATTACH type="full"]10119[/ATTACH] Internal [ATTACH type="full"]10118[/ATTACH] Basalts typically retain the dark grey/black due to the manganese & pyroxene, weathering or "rusting" from the outside. The sample also appears not to be fine grained enough for basalt & high in silica content (quartz grains). Basalt is low in silica. Hard to tell from a photo on phone & not a lot of info. If it's grainy & friable (crumbly) when broken I'm sticking with my initial amatuer guess 😄 Either way it's definitely iron mineral content giving it the red colour. [/QUOTE]
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Gemstones, Minerals & Fossils
Gemstones and Minerals
❓Your Mineral Identification Questions answered here
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