Tourmaline<\/a> is a group of borosilicate minerals with a complex chemical composition and a wide variety of colours. It occurs in virtually every colour of the rainbow, including pink, green, blue, black and multi-coloured combinations. This variety makes tourmaline one of the most popular gemstones in the jewellery world.<\/p>\n Tourmaline usually forms in pegmatites and metamorphic rocks. Major deposits include Brazil, Afghanistan, Mozambique, Nigeria and the United States. The chemical formula varies, but a general form is (Ca,K,Na)(Al,Fe,Li,Mg,Mn)\u2083(Al,Cr,Fe,V)\u2086(BO\u2083)\u2083(Si,Al,B)\u2086O\u2081\u2088(OH,F)\u2084. The hardness is between 7 and 7.5 on the Mohs scale.<\/p>\n Popular varieties include black tourmaline (sch\u00f6rl), pink tourmaline (rubellite), green tourmaline (verdelite) and watermelon tourmaline (pink interior, green rim).<\/p>\n Sources: <\/strong> Black Tourmaline Heart from China<\/p>","protected":false},"featured_media":61909,"template":"","meta":{"_acf_changed":false,"site-sidebar-layout":"default","site-content-layout":"","ast-site-content-layout":"default","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","theme-transparent-header-meta":"","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"default","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"var(--ast-global-color-4)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}}},"soort":[],"product_brand":[],"product_cat":[2989],"product_tag":[],"class_list":{"0":"post-61921","1":"product","2":"type-product","3":"status-publish","4":"has-post-thumbnail","6":"product_cat-harten-per-stuk","7":"pa_herkomst-china","8":"pa_maat-4-cm","9":"pa_soort-toermalijn","10":"pa_soort-zwarte-toermalijn","11":"pa_verkoopeenheid-per-stuk","12":"pa_vorm-hart","13":"desktop-align-center","14":"tablet-align-center","15":"mobile-align-center","16":"ast-product-gallery-layout-horizontal-slider","17":"ast-product-gallery-with-no-image","18":"ast-product-tabs-layout-horizontal","20":"first","21":"instock","22":"taxable","23":"shipping-taxable","24":"product-type-simple"},"acf":[],"_links":{"self":[{"href":"https:\/\/www.ruschmineralen.nl\/en\/wp-json\/wp\/v2\/product\/61921","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.ruschmineralen.nl\/en\/wp-json\/wp\/v2\/product"}],"about":[{"href":"https:\/\/www.ruschmineralen.nl\/en\/wp-json\/wp\/v2\/types\/product"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.ruschmineralen.nl\/en\/wp-json\/wp\/v2\/media\/61909"}],"wp:attachment":[{"href":"https:\/\/www.ruschmineralen.nl\/en\/wp-json\/wp\/v2\/media?parent=61921"}],"wp:term":[{"taxonomy":"soort","embeddable":true,"href":"https:\/\/www.ruschmineralen.nl\/en\/wp-json\/wp\/v2\/soort?post=61921"},{"taxonomy":"product_brand","embeddable":true,"href":"https:\/\/www.ruschmineralen.nl\/en\/wp-json\/wp\/v2\/product_brand?post=61921"},{"taxonomy":"product_cat","embeddable":true,"href":"https:\/\/www.ruschmineralen.nl\/en\/wp-json\/wp\/v2\/product_cat?post=61921"},{"taxonomy":"product_tag","embeddable":true,"href":"https:\/\/www.ruschmineralen.nl\/en\/wp-json\/wp\/v2\/product_tag?post=61921"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
Mindat.org<\/a>, Gemdat.org<\/a>, Wikipedia - Tourmaline<\/a><\/small><\/p>","protected":false},"excerpt":{"rendered":"