<?xml version="1.0" encoding="utf-8"?><!DOCTYPE Zthes SYSTEM "http://zthes.z3950.org/xml/zthes-05.dtd">  <Zthes><term><termId>31344486</termId><termName>marcasite</termName><termType>PT</termType><termNote><![CDATA[ A mineral with the same composition as pyrite (fool's gold) but differing in crystal structure. It can be faceted like a gemstone; it was popular in the 1920s to 1930s, usually set in sterling silver. It is commonly found as nodules and concretions in sedimentary rocks. ]]></termNote><termCreatedDate>2026-03-30 20:32:54</termCreatedDate><relation><relationType>BT</relationType><termId>31320469</termId><termName>mineral</termName><termType>PT</termType></relation><relation><relationType>BT</relationType><termId>31376754</termId><termName>gemstones by specific type</termName><termType>PT</termType></relation><relation><relationType>RT</relationType><termId>31344487</termId><termName>pyrite</termName><termType>PT</termType></relation><relation><relationType>RT</relationType><termId>31457278</termId><termName>white iron</termName><termType>PT</termType></relation></term>  </Zthes>