Lava Rock vs Pumice

BrianBay9

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Many forms of pumice are more porous and lighter than lava - hold more water than lava. Many forms of pumice can be crushed between your fingers. Others are pretty darn firm, more similar to what I think of as lava rock. From what I've seen of pumice and lava, I think there's a spectrum between the two.
 

Bonsai Nut

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The pumice that I use is grey in color and is less dense than the red lava rock that I use. The pumice seems to be more absorbent than the lava rock, but I have not tested it.
 

just.wing.it

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I'm using Bonsai Jack's Maroon Lava and White Pumice together this year....I also mixed in Haydite with some of them.

So far I like what see.
The Lava, for me, is generally a larger particle size, and the Pumice fills the gaps.

Also, Bonsai Jack's White Pumice doesn't crumble in your grip...
No dust to speak of, while sifting...
Very pleased.
 

just.wing.it

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Pumice is silica, volcanic glass. It is the froth that boils to the top of the caldron. The cinder or lava rock is everything else, depending on how it's blasted out of the volcano.
What's happening in HI might just have a silver lining after all!

..... too soon.... Sorry.
 
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Pumice is silica, volcanic glass. It is the froth that boils to the top of the caldron. The cinder or lava rock is everything else, depending on how it's blasted out of the volcano.
Not sure about pumice being volcanic glass... I have always heard that obsidian is volcanic glass...

I believe that in terms of chemistry, pumice and scoria are very similar but the former is much lighter and porous (and it floats). My experience, pumice retains a lot more than scoria... But this may differ among harvesting places.

Never heard of a black pumice though. Always grey/white. Scoria yes. It can be either black or red.

@markyscott can you clarify this?
 

River's Edge

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Hi,
im still learning. I bought a pick and mix of bonsai stuff and in it was 'Black lava pumice' is this different from Lava rock?
looking on https://www.bonsaiempire.com/basics/bonsai-care/advanced/bonsai-soil they are listed differently but the role sounds the same? hard, inorganic to encourage roots and drainage?
have i missed something?
You have discovered that not everyone uses the terms correctly! Pumice, Lava, scoria are some of the terms used to describe inorganic substances of volcanic origin. They vary by density, color, element composition, vesicle size, water retention capacity. If you want to go through the technical information just google the " CANLAVA" website. It has specific scientific information for the descriptive terminology.
 

TyroTinker

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Not sure about pumice being volcanic glass... I have always heard that obsidian is volcanic glass...

I believe that in terms of chemistry, pumice and scoria are very similar but the former is much lighter and porous (and it floats). My experience, pumice retains a lot more than scoria... But this may differ among harvesting places.

Never heard of a black pumice though. Always grey/white. Scoria yes. It can be either black or red.

@markyscott can you clarify this?

There are many types of volcanic glass, obsidian is just one. But I don't have and answer about pumice or lava rock, and whether or not they are one of the types
 

Hawke84

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yikes, didnt know i'd start something :D
ok this is what ive got:
20180505_080132.jpg20180505_080137.jpg

and i got this with it, is this pumice? google says grit but it looks like and airy

20180505_080501.jpg20180505_080504.jpg
 
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Is it just me or does the "black volcanic pumic" look like its mixed with LECA?
Yes a bit. But i've seen scoria that looks like that, so not sure. The black stuff is definitely scoria. The other bag does look like pumice although all pumice here is grey.
 

TyroTinker

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Right at the source (Kilauea ) but 4Kfeet above the action. 176 quakes yesterday! Running underground and burping into Leilani estates near the coast. Feeling pretty shaken up.
Hang in there! It will work out in the end.

My wife and I honeymooned on the big island and it just happened to be the 1st time in 50 years that a hurricane hit. Spent our honeymoon in a shelter with 30-40 other people :rolleyes: still had a blast
 

just.wing.it

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Right at the source (Kilauea ) but 4Kfeet above the action. 176 quakes yesterday! Running underground and burping into Leilani estates near the coast. Feeling pretty shaken up.
Wow, watch out for the sulfur dioxide, I've got a whiff of that stuff before, nasty, will kill you quick.
Stay safe!
 
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