Question about Floor Insulation

[Joaam]

Hello great community, this is my first post in this forum, I apologize because I'm not sure if this question has already been asked and answered, I did read several threads with similar topics but couldn't find an answer that was conclusive to my concern, this are my facts :
- I'm building a 40" Corner oven on a second floor of an open area.
- I managed to find in my country "Honduras, Central America" the Firebrick's, Mortar, refractory cement and the blanket but had no luck with the Board and the vermiculite or perlite.

I'm concerned about the insulation in the floor because of the lack of board and/or Vermiculite-Perlite, so mi question is about which other options do I have, I was thinking about 3 :
1) Make a Pour on the floor with a 2" or 3" layer of refractory cement above the concrete base.
2) Place over the concrete base a 2" or 3" layer of the ceramic blanket and a thin 1" layer of refractory cement.
3) Place over the concrete base a 2" or 3" layer of the ceramic blanket and cover it with sand.
Please advise me if any of this options are not adequate and if there are any other option given the limited materials I have.

Thanks a lot for your answers and your great, great forum.