Unknown Sand... Calcium Based ? HELP

[baboon]

Hi everyone

I bought this kind of sand from a african aquarium Owner at a very very low price.

The idea is to use it on my reef, but after i done my research, i cant determine with safety, if this sand is totally reef safe (carbonate calcium) or it may be silica based.
It is round shaped like small fish eggs, white (not brilliant)

I visit all marine substrate brands i know and didnt find anything similar (caribsea has a sugar sized oolite bur doesnt look very similar)
The guy that i bought this sand from, only remembers that it was expensive :lmao: and in bags Lol.

It looks like ooids, (like this picture from http://blogs.agu.org/)
http://blogs.agu.org/georneys/files/2011/09/IMG_0006-764x1024.jpg.

Can anyone help to determine what kind of sand is this, and can i use it safely on a reef?

Thanks on advanced

 

[bob1968]

Drop some in vinager if it bubbles it's calcium

 

[baboon]

Thanks I´ll try that!

Wonder what brand sells this sand...

 

[JB63]

Looks like couscous (pasta) to me ... but seriously, are the grains very smooth/rounded? Is it porous?

Definitely not silica ... as the Silica-based sand I know has a bit darker color, not all grains are the same color, and the grains are usually much finer than what you're showing.

 

[mcgyvr]

oolite