Hello, I am new to the gem world but I love this world and that’s why I invest time and money in it. I am trying to find what type of gems I got at the practical exam and I am at the 2nd gem and already encountered problems. The refractometer gave me 1.61- 1.615 reading so it’s a uniaxial positive. I have to choose between a tourmaline which is uniaxial - and a pink topaz which is biaxial +. The other two can’t be because one is sapphire, other rose quartz which ilhas RI than 1.6.
Can someone clarify the problem please 