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I found these 2 at the beach on the east coast of the North Island in New Zealand.

The white one is beautiful, it sparkles and glimmers and even the brown/pink veins through it sparkle, but it's quite fragile; I can break some off with my fingernail. It reflects the light quite bright as well.

light coloured rock light coloured rock2

The dark one is very hard, looks yellow/brown when held up to the sun and has thick white lines through some of it. Found a couple of these. I thought it was smoky quartz but have been told it's not. It doesn't reflect the light it seems to take it in.

dark coloured rock dark coloured rock2!enter image description here

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  • $\begingroup$ Does the second one have a yellow/blue reflections at certain angle? $\endgroup$ – Gabija Jan 16 '18 at 11:10
  • $\begingroup$ The white one? No there's no colour reflecting from it, it has an Opal gleam to it but without the colours. And the pink and brown veins through it have chunks of glass looking crystal. $\endgroup$ – Jemma Michelle Jan 16 '18 at 22:09
  • $\begingroup$ the dark one looks like chert/flint but the white one is so washed out by the light source it could be anything. Note there are beds of mixed chert and limestone in NZ. $\endgroup$ – John Jan 20 '18 at 5:36
  • $\begingroup$ Did you look at all 3 photos of the light one? Only one is taken in light. It looks exactly as it does in the second photo, which is where you can see the pink and brown lines. In the first photo is the other side of the rock with less colour to it. And the third is in the sunlight so you can see how it looked when I found it, just a bright white thing on the beach $\endgroup$ – Jemma Michelle Jan 20 '18 at 5:41
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The dark one looks like chert, there are known deposits in New Zealand (click on the dark variety).

the white is washed out by the light making it hard to see, it could be limestone or marble but it could be white quartz or a dozen other things as well, without a better picture it is hard to say. An acid test would be the best way to check.

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  • $\begingroup$ The dark stone is not flint. And as I stated in the other comment, only one photo is taken in the light so please look at the other 2. It is not quartz nor marble, and you can see that in the other 2 photos. It's also too fragile to be either one of them. $\endgroup$ – Jemma Michelle Jan 20 '18 at 6:06
  • $\begingroup$ why do you beleive it is not flint, or more specifically not chert? $\endgroup$ – John Jan 20 '18 at 6:13
  • $\begingroup$ breaking off with your fingernail is a measure of brittleness not hardness. $\endgroup$ – John Jan 20 '18 at 6:19

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