The Seventeen Treasures: Chapter one- Discovery

The summer heat was nearly unbearable. It must have been a hundred ten degrees outside. Her camp counsellor was clearly bugged by the extreme weather also. Her best friend Cary stood beside her. Cary had long dark brown hair, at about seven inches below her shoulders. Her green forest-eyes shone brilliantly in the sun. We were set upon the High Summit trail. Too bad we weren't really there. We were alone on this trail, with a very accurate map, GPS, and a cell phone. We had several water bottles and food. We were on a scavenger hunt. We were supposed to find a deer antler, bear claw, and a maple leaf before we were allowed to go into the heavenly air-conditioning of our cabins. My spirit perked up as a soft breeze blew my short blonde hair a little. We were gazing at the map so hard that I almost didn't notice a big pile of leaves.
"Maybe there's a maple leaf in that pile," I say to Cary. I walk a few feet off the path and stick my hand in the pile. I move it around. I was shocked when I felt cool marble.
But what would marble be doing in a place like this? I call cary over and we examine it. We clear the leaves and a small 3-foot tall marble pedastal rose from the ground. We jumped back a little. A small,wooden table appeared in front of the pedastal. On it was fifteen bones organized into an odd pattern. The first one was a square with a straight line pointing up. The second was a straight line pointing sideways. Then there was one pointing down, to the right. On a plaque attatched to the table read:
Here lie fifteen bones of
Ancient men. Take away
Six, but still leave ten.
This is easy! She thought. She took away six bones so that the pattern spelled the word ten. The bones vanished. The table vanished. The pedastal vanished. The feeling of cold, hard metal appeared in her hand. Only it wasn't cold hard metal. It was a green-blue gem with seventeen sides. One side had a odd type of writing on it, and below that was a sheild. What was this?