easy fix --to sort out white quartz ( which is basically worthless) --from diamonds (which can be very valuable ) there are diamond testers ( about 20 bucks at Walmart.com) --which will work on raw diamonds -- --so that you do not have to "trust" anyone simple --get it and find out for yourself what you got----- that said --often in cement small gravel type rocks are mixed into the slurry mix --some of them in the mixture might be various small / tiny semi precious stones -- personally I think the clear ones are ....clear white quartz --but who knows
I found some nice garnets while gem grubbing up in north GA with my wife by buying a 5 gallon bucket of "rocks" and sorting thru them at one of the tourist trap goldmine spots -- also some huge light blue sapphires stones (note the 5 gallon buckets of "rocks" are imported from North Carolina ) -- --and a decent sized chunk of lower quality ( milky white /green) emerald -- I showed them to my wife who said "are you sure they just look like rocks to me ?" --I laughed and said yes i'.m quite sure --had to take her to the gem guy in town ( that works at one of the so called "mines" he helps folks ID what they find in their buckets in case they find some worth making into a ring) to have him say yes they are indeed nice make into a ring quality garnets and emerald --I got 3 rings made 2 nice garnet rings for my wife and daughter and the emerald for my son...before cutting and polishing most gemstones do not look like much honestly --they just look like a "rock"
it takes a skilled keen eye to spot many semi precious --and precious stones -- and figger out their not just a worthless rock --diamonds and clear quartz can be tough since both are clear and quite hard and look similar --most diamonds require a volcanic flue spot to be found as it takes lots of heat and pressure to turn plain old coal (carbon) into diamonds
I am now 57 and been collecting various rocks and minerals since I was 7 --- so after 50 years I know a thing or two about "rocks and minerals"
concrete.
