Software used: Bruker Eva version 7.0 with PDF Release 1999 database.
Various search strategies tried, but mainly with the elements suggested,
using full patterns.


Summary of results:


Sample 1
Possibly quartz or berlinite:
76-558         Fluoroapatite       Ca5(PO4)3F
76-228         Berlinite      AlPO4
29-696         Sidenite       FeCO3
44-1415        Lepidocrocite       FeO(OH)
33-863         Souzalite      (Mg,Fe)3(Al,Fe)4(PO4)4(OH)6·2H2O
82-511         Quartz              SiO2


Sample 2
searching on Si + O + possibly F + organic, no good fits found. However
it might be related to:
48-475    Silicon Oxide Quinuclidine Fluoride Octadecasil    C14H24F2N2O40Si20/20SiO2·2(C7H12NF)


Sample 3
There is only one pattern with the molecular formula C13H10N4O4 in
PDF release 1999 and it is not present in this diffraction pattern.


Sample 4
23-0333   Lead Oxide Sulfate       Pb5O4SO4/PbSO4·4PbO
29-0781   Lead Oxide Sulfate Hydrate     Pb4O3SO4·H2O
78-1666   Lead Oxide               PbO