Significance and Use
3.1 These test methods can be used to ensure that the chemical composition of the glass sand meets the compositional specification required for this raw material.
3.2 These test methods do not preclude the use of other methods that yield results within permissible variations. In any case, the analyst should verify the procedure and technique used by means of a National Institute of Standards and Technology (NIST) standard reference material or other similar material of known composition having a component comparable with that of the material under test. A list of standard reference materials is given in the NIST Special Publication 260, current edition.
Scope
1.1 These test methods cover the chemical analysis of glass sands. They are useful for either high-silica sands (99 % + silica (SiO2)) or for high-alumina sands containing as much as 12 to 13 % alumina (Al2O3). Generally nonclassical, the test methods are rapid and accurate. They include the determination of silica and of total R2O3  (see 11.2.4), and the separate determination of total iron as iron oxide (Fe2O3), titania (TiO2), chromium oxide (Cr2O3), zirconia (ZrO2), and ignition loss. Included are procedures for the alkaline earths and alkalies. High-alumina sands may contain as much as 5 to 6 % total alkalies and alkaline earths. It is recommended that the alkalies be determined by flame photometry and the alkaline earths by absorption spectrophotometry.
1.2 These test methods, if followed in detail, will provide interlaboratory agreement of results.
Note 1: For additional information, see Test Methods C169 and Practices E50.
1.3 The test methods appear in the following order:
| Procedures for Referee Analysis: | Section |
|
|
|
|  Silica (SiO2)—Double Dehydration | 10 |
|  Total R2O3—Gravimetric | 11 |
|  Fe2O3, TiO2, ZrO2, Cr2O3, by Photometric Methods and | 12 – 17 |
|  Preparation of the Sample for Determination of Iron | 12 |
|  Iron Oxide (as Fe2O3) by 1,10-Phenanthroline Method | 13 |
|  Titania (TiO2) by the Tiron Method | 14 |
|  Alumina (Al2O3) by the CDTA Titration Method | 15 |
|  Zirconia (ZrO2) by the Pyrocatechol Violet Method | 16 |
|  Chromium Oxide (Cr2O3) by the 1,5-Diphenylcarbo- | 17 |
|
|
|
| Procedures for Routine Analysis: |
|
|
|
|
|  Silica (SiO2)—Single Dehydration | 19 |
|  Al2O3, CaO, and MgO—Atomic Absorption Spec- | 20–25 |
|  Na2O and K2O—Flame Emission Spectrophotometry | 26-27 |
|  Loss on Ignition (LOI) | 28 |
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.
