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Let's Rock => Rock Talk => Topic started by: ileney on September 06, 2017, 02:26:26 PM

Title: Indigo gabbro undercutting
Post by: ileney on September 06, 2017, 02:26:26 PM
Anyone have experience with Indigo gabbro undercutting? Any suggestions? The dark grey metallic parts are undercutting wildly, even at only 600 Nova. The stuff is very weird. Mixed in with the shiny dark gray is what looks like a blue/lavenderish agate and maybe some moonstone or white labradorite. It's still an interesting stone with or without the undercutting. It has a very weird, organic, almost nautical vibe to it. My cut stone somehow reminds me of seashells or coral. I'm not sure if I want to bother stabbing the rest of the small stones I have as it undercuts so much.
Title: Re: Indigo gabbro undercutting
Post by: vitzitziltecpatl on September 06, 2017, 05:27:19 PM
Hmmm. I seem to remember some softer spots in what we have. More so in one end of the chunk/slabs. We were able to cut and polish other areas okay. Maybe later I can get a pic of the one cab we still have on hand from it.
Title: Re: Indigo gabbro undercutting
Post by: lithicbeads on September 06, 2017, 07:48:21 PM
Gabbro can have a lot of magnesium in it and it is very soft.
Title: Re: Indigo gabbro undercutting
Post by: ileney on September 08, 2017, 06:25:32 AM
Thank you. Maybe it is Magnesium. I am rethinking this because it doesn't feel undercut when I touch it. It just looks undercut, if you know what I mean. Will have to post a picture later to show. It's a weird stone IMO.
Title: Re: Indigo gabbro undercutting
Post by: lithicbeads on September 08, 2017, 06:48:22 AM
Gabbro is very variable in look.I cut some yesterday from the beach here in Washington and it was feldspar and hornblende and looks just as good unpolished as it does polished.We have lots of it here that you could call supersized.It has the same white and black mix but instead of the alternating black and white areas being 1/8 to 1/4 inch in size the materials get to be inches across  and irregular in distribution.