I was going to comment on this yesterday, but got distracted. There is no 'best' of anything. There is only 'best' relative to my tastes and preference, and 'best' for the money.
Since you never mentioned how much money you want to spend, we can't really say what is best. So far you have had comments that include everything from cement block to expensive sand filled steel stands.
Also, a lot depends on your speakers. You want the speaker roughly at 'ear' height in your listening space. Presumable you will be sitting in a chair, so ear height when you are sitting down.
My speakers are 26 inches tall. I made speaker stands by buying 12 inch square marble tile and epoxy gluing them together into a box. The puts them a little below ear level, but it works out fine.
My previous speaker stands were 12"x12"x3.75" cement Patio blocks. I covered them on 5 sides with white marble vinyl floor tile and used two per speaker.
Both worked very well for me; they are solid and aesthetically pleasing. Cost? $3.00 each for the 'marble' patio blocks. $5.00 each for the genuine marble boxes.
Note: I could have done the same thing in genuine granite. Of course, the selection I had wasn't great. To get genuine marble or granite for about $1.00 per square foot, you have to take what is on sale. Normally, it is $5.00 to $15.00 per square foot depending on the style and rarity of the marble.
The same thing could be done with standard ceramic floor tile. If you need it taller than a foot, you can make a simple wood frame out of 2"x2" lumber and glue the tile to the wood, cap the ends with MDF or plywood, and if you are worried about resonance, fill the boxes with fiberglass.
If you want to do it on the super cheap, build the wood frame and glue on vinyl floor tile. Though, you will find that ceramic is only about $.50 more per tile than vinyl.
Obviously I'm working on a very restricted budget.
But my point is, there is no 'best', only best for the money.
Steve/bluewizard