I know there have been dozens of discussions about this, but I can't seem to find my specific questions answered when I search the forums or the Internet. Wondering if someone here can help!

I'm trying to lighten my concrete yet still keep the strength. I'm making concrete stools, end tables and yard ornaments. The surfaces will all be either stained or covered with mosaic, thus I am not out for the finish one gets with hypertufa, nor will I be doing any carving.

Really, I just want to make something that's as sturdy as the concrete I've been working with, but a little lighter.

What's confusing to me is whether or not I need to add something to strengthen the mix if I start adding perlite. I've found a recipe that calls for 1 part Concrete, 1 part Sand, 2 parts Perlite, but in the same conversations people casually toss out comments about "admix", "latex", and "plastic fibers". I'm not clear on whether that's required, and if so, what are they exactly and where would I get them? I've also read that the perlite I'm looking for isn't the perlite I can buy in the potted plant section at Lowes. Is that right? Could I avoid additives if I went with 1 part Cement, 2 parts sand and one part perlite? Even a little lighter would be nice if it doesn't compromise the structure.

Like I said, I love what I've been making from the standard mortar mix, but I'd just like it a little lighter. Seems like an easy thing to look up on the internet, but I either suck at searching or there's no straight answer!

Thanks in advance for any advice you can offer!