What is salt that has a green colour?

[Nicol76]

TL;DR Summary

green salt

What are salt that have green colour?

 

[etotheipi]

For starters, $\text{Fe}\text{SO}_4 \cdot 7\text{H}_2\text{O}$ and $\text{Cu}\text{CO}_3$.

 

[Merlin3189]

What ions have green colour?
What is a salt?

Ion colours
Edit: but having looked carefully at this, I think they got ferrous and ferric mixed up!
Maybe try ion colours2

 

[Vanadium 50]

Are we sure we are talking about salt in the chemistry sense and not the cooking sense? There are green salts one can get from, I think, Hawaii.

 

[jim mcnamara]

Mineral blocks come in colors so the farmer can tell the type of block, like low iodine salt block.

My worry about this vague question - post: do not use green salt on food. Period.

Copper salts have pretty green colors, blue-green and also blue. Depends on which one.

Pictures of some copper minerals here:

https://www.dreamstime.com/major-co...urite-chrysocolla-chalcopyrite-image127454696

 

[jim mcnamara]

@Vanadium 50 - ad for Hawaiian green sea salt
https://www.gourmetfoodstore.com/gourmetfoodstore-com-hawaiian-green-bamboo-sea-salt-coarse-13098

My post warning above is wrong if we mean this kind of salt.

 

[Nicol76]

Thank you everyone for your help. Yes I meant salt in chemistry. Sorry Merlin, English is not my first language and I probably used the wrong word. My question is about ionic compounds.

 

[TeethWhitener]

Your screen name is apt, @Nicol76. The first one I thought of was nickel chloride.

 

[Merlin3189]

@Nicol76 No, you were correct.
I asked "what is a salt" to check you know it as an ionic compound and so you are looking for the ions with colour green.

Coloured ions are transition metals, because of their electronic structure.
$Fe^{2+}$ and $Ni^{2+}$ are predominantly green.

Other ions which are not generally green, are green in some compounds $Cu^{2+}$ usually blue, is green in basic copper carbonate , and $Cr^{2+}$ changes from its usual violet to green in chromium hydroxide.

That is because the energy levels are modified by surrounding ions such as hydroxide. This is shown nicely with copper sulphate, where the $Cu^{2+}$ ions are a pleasant pale blue in the hexahydrate crystals or in aqueous solution. There the $Cu^{2+}$ are surrounded by water molecules. If excess ammonia is added to the solution, the $Cu^{2+}$ become surrounded by $NH_3$ molecules and turn a glorious deep blue.

 

[Nicol76]

just saw your reply. Thank you so much, this is really useful.

 

[nettleton]

Most chromium salts are green.