How to test the presence of shabu

A white crystalline substance was submitted to the crimelab lab office for testing, and our supervisor showed us how to test the presence of shabu. First,the substance was weighed. IN the test, three reagents were used, Simon's Reagent 1,2 & 3. We also used a tawas to compare its reaction and the white crystalline substance's reaction to the three reagents. When the Simon's reagent 1 was dropped , the substance dissolved but the tawas didn't. In the second reagent, no reaction happened to the substance but the tawas bubbled. The third reagent wil then determine the color. Blue is the expected color if shabu is present and if not it'll be just color orange. When the Simon's reagent 3 was dropped, the tawas was just color orange, but the substance changed to color blue which indicates the presence of shabu.
Marquiz Reagent can also be used to determine the presence of shabu. But it will take about 30 mins. for the substance to change from orange to yellowish green which indicates the presence of shabu.