I usually use this site.
But I think that found a problem with that site.
Because TiO2 values are different from other methods.
Like this,
my site: TiO2 0.59 (wt.%) -> Ti 5678 (ppm)
other methods: TiO2 0.59 (wt.%) -> Ti 3549 (ppm)
My site: http://www.marscigrp.org/elconv.html#ti
Others methods
1) http://www.marscigrp.org/oxtoel.html
2) Excel sheet (attached to this text)
What is wrong with my method?