[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"detail-sidebar-cat-0-en-105":3,"doc-seo-657660-105":59,"doc-detail-657660-en":130},{"code":4,"msg":5,"data":6},0,"success",[7,13,18,23,28,33,38,43,48,51,55],{"id":8,"doc_module":4,"doc_module_name":9,"category_name":10,"show_sort_weight":11,"slug":12},1,"Document","Story & Novel",90,"story-novel",{"id":14,"doc_module":4,"doc_module_name":9,"category_name":15,"show_sort_weight":16,"slug":17},2,"Literature",80,"literature",{"id":19,"doc_module":4,"doc_module_name":9,"category_name":20,"show_sort_weight":21,"slug":22},4,"Exam",70,"exam",{"id":24,"doc_module":4,"doc_module_name":9,"category_name":25,"show_sort_weight":26,"slug":27},5,"Comic",60,"comic",{"id":29,"doc_module":4,"doc_module_name":9,"category_name":30,"show_sort_weight":31,"slug":32},6,"Technology",50,"technology",{"id":34,"doc_module":4,"doc_module_name":9,"category_name":35,"show_sort_weight":36,"slug":37},7,"Healthcare",40,"healthcare",{"id":39,"doc_module":4,"doc_module_name":9,"category_name":40,"show_sort_weight":41,"slug":42},8,"Research & Report",30,"research-report",{"id":44,"doc_module":4,"doc_module_name":9,"category_name":45,"show_sort_weight":46,"slug":47},9,"Religion & Spirituality",20,"religion-spirituality",{"id":46,"doc_module":4,"doc_module_name":9,"category_name":49,"show_sort_weight":46,"slug":50},"World Cup","world-cup",{"id":52,"doc_module":4,"doc_module_name":9,"category_name":53,"show_sort_weight":52,"slug":54},10,"Lifestyle","lifestyle",{"id":56,"doc_module":4,"doc_module_name":9,"category_name":57,"show_sort_weight":24,"slug":58},19,"General","general",{"code":4,"msg":60,"data":61},"ok",{"site_id":62,"language":63,"slug":64,"title":65,"keywords":66,"description":67,"schema_data":68,"social_meta":123,"head_meta":125,"extra_data":127,"updated_unix":129},105,"en","perception-angle-tables-for-ri-160-240-free-eye-design","Perception - Angle Tables for RI 1.60-2.40 - Free Eye Design","","Gemstone eye design “Perception” by Andrew Ian Brown-March 2020 provides free-cutting guidance with angle optimization across refractive indexes (RI) 1.60 to 2.40. The publication explains pavilion and crown facet configurations, including symmetry details, RI range diagrams, and material notes on cutting accuracy. It includes index-based instructions and detailed angle tables for pavilion facets (A–D / FCP) and crown facets (A–D / multiple facet series) with stepwise “meet” and “maintain” directives to achieve tier depths, girdle width, and proper facet depth for selected stones.",{"@graph":69,"@context":122},[70,84,105],{"@type":71,"itemListElement":72},"BreadcrumbList",[73,77,79,82],{"item":74,"name":75,"@type":76,"position":8},"https://docshare.wps.com","Home","ListItem",{"item":78,"name":9,"@type":76,"position":14},"https://docshare.wps.com/document/",{"item":80,"name":30,"@type":76,"position":81},"https://docshare.wps.com/document/technology/",3,{"item":83,"name":65,"@type":76,"position":19},"https://docshare.wps.com/document/perception-angle-tables-for-ri-160-240-free-eye-design/657660/",{"url":83,"name":65,"@type":85,"image":86,"author":91,"headline":65,"publisher":94,"fileFormat":97,"inLanguage":63,"description":67,"dateModified":98,"datePublished":99,"encodingFormat":97,"isAccessibleForFree":100,"interactionStatistic":101},"DigitalDocument",{"url":87,"@type":88,"width":89,"height":90},"https://docshare.wps.com/thumbnails/perception-angle-tables-for-ri-160-240-free-eye-design/657660.png","ImageObject",300,407,{"name":92,"@type":93},"putri.kecil17","Person",{"url":74,"name":95,"@type":96},"DocShare","Organization","application/pdf","2026-10-30","2026-10-26",true,{"@type":102,"interactionType":103,"userInteractionCount":24},"InteractionCounter",{"@type":104},"ViewAction",{"@type":106,"mainEntity":107},"FAQPage",[108,114,118],{"name":109,"@type":110,"acceptedAnswer":111},"What refractive index range does the Perception eye design support?","Question",{"text":112,"@type":113},"The design is optimized for RI from 1.60 to 2.40, with separate angle tables grouped by RI intervals.","Answer",{"name":115,"@type":110,"acceptedAnswer":116},"Why is the design not recommended for quartz?",{"text":117,"@type":113},"The author states the design will not optimize for quartz, and it is recommended instead for lightly saturated materials, especially at lower RI.",{"name":119,"@type":110,"acceptedAnswer":120},"Which cutting accuracy points does the guide emphasize?",{"text":121,"@type":113},"The guide advises careful cutting of the C2 facets that are cut to depth, noting that the remaining crown facets should then fall into place.","https://schema.org",{"og:url":83,"og:type":124,"og:title":65,"og:site_name":95,"og:description":67},"article",{"robots":126,"canonical":83},"index,follow",{"doc_id":128,"site_id":62},657660,1793069709,{"code":4,"msg":5,"data":131},{"doc_id":128,"user_id":132,"nickname":92,"user_avatar":133,"doc_module":4,"category_id":29,"category_name":30,"doc_title":65,"doc_description":67,"doc_content":134,"file_id":135,"file_url":136,"file_type":137,"file_size":138,"view_count":24,"is_deleted":4,"is_public":8,"is_downloadable":8,"audit_status":8,"page_count":24,"language":139,"language_code":63,"site_id":62,"html_lang":63,"table_of_contents":140,"faqs":141,"seo_title":142,"seo_description":67,"update_tm":143,"read_time":144},962094509873,"https://ap-avatar.wpscdn.com/davatar_3d24733baf745e90a7e4bdd5f77d97b2","Perception  \n© Andrew Ian Brown-March 2020  \nPerception 54 48 42  \n60 36  \n© Andrew Brown-March 2020  \n66  \nDesign Information  \n30  \n| Pavilion facets\u003Cbr>Girdle facets\u003Cbr>Crown facets\u003Cbr>Total facets\u003Cbr>Index gear\u003Cbr>Symmetry\u003Cbr>RI range\u003Cbr>RI diagram | 48\u003Cbr>24\u003Cbr>72+1\u003Cbr>145\u003Cbr>96\u003Cbr>2-fold\u003Cbr>mirror image\u003Cbr>1.60 to 2.40*\u003Cbr>1.60 to 1.70 |\n| --- | --- |\n| L/W = 1.413\u003Cbr>U/W = 0.423\u003Cbr>C/W = 0.319 | T/W = 0.423\u003Cbr>P/W = 0.661\u003Cbr>V/W3 = 0.496 |\n\n* can be optimized further for materials above RI 2.40.  \n72  \n78  \nC  \nP  \nIn appreciation to fellow faceters who have enjoyed my books, I have decided to provide this eye design free. I have created angle optimizations that produce a face up pattern that I really like for a range of refractive indexes (RI) from 1.60 to 2.40. Unfortunately the design will not optimize for quartz. Note the diagram above shows the angles for RI  \n1.60 to 1.70, this optimization has the highest crown. You will notice in the angle tables on the following pages that the crown angles drop as the RI increases. This design will darken gemstone rough, so I would only recommend cutting it in lightly saturated materials, especially at lower RI. I did not find this design hard to cut, but take care to cut accurately the C2 facets that are cut to depth and hopefully the rest of the crown facets should all fall into place. The design ‘Perception’ in this publication is for personal use and not to be publish elsewhere without the author’s permission. It can be download via the author’s website. [https://facetingdesigns.com/](https://facetingdesigns.com/)  \nI would also like to acknowledge Bob Keller's \"Cleopatra Eye\" design which has a similar style to this design. Although the crown, pavilion and girdle outline are significantly different.  \nRI = 1.61 Topaz  \n\n| \u003Cbr>RI = 1.76 Corundum |\n| --- |\n| \u003Cbr>RI = 2.16 CZ |\n| \u003Cbr>RI = 2.37 Sphalerite |\n\n3  \nPerception  \n© Andrew Brown-March 2020 Angles for RI 1.60 to 2.00  \nAIB126  \nP1  \n\n| \u003Cbr>\u003Cbr>\u003Cbr>\u003Cbr>\u003Cbr>\u003Cbr>\u003Cbr>\u003Cbr>\u003Cbr>\u003Cbr>\u003Cbr>\u003Cbr>\u003Cbr>\u003Cbr>\u003Cbr>\u003Cbr>\u003Cbr>| \u003Cbr>\u003Cbr>\u003Cbr>\u003Cbr>\u003Cbr>\u003Cbr>\u003Cbr>\u003Cbr>\u003Cbr>\u003Cbr>\u003Cbr>\u003Cbr>|\n| --- | --- |\n| \u003Cbr>\u003Cbr>\u003Cbr>\u003Cbr>\u003Cbr>\u003Cbr>\u003Cbr>\u003Cbr>\u003Cbr>\u003Cbr>\u003Cbr>\u003Cbr>\u003Cbr>\u003Cbr>\u003Cbr>\u003Cbr>\u003Cbr>| \u003Cbr>\u003Cbr>\u003Cbr>\u003Cbr>\u003Cbr>P1 P1\u003Cbr>P1 P3\u003Cbr>P1 \u003Cbr>P1\u003Cbr>\u003Cbr>\u003Cbr>\u003Cbr>\u003Cbr>\u003Cbr>\u003Cbr>\u003Cbr>\u003Cbr>\u003Cbr>\u003Cbr>\u003Cbr>|\n\nG1  \nG2  \nP4 P5  \nP6   \nG3  \n G4  \nG5  \nG6  \nP2  \nP7  \nPavilion *A = RI 1.60 to 1.70 B = RI 1.70 to 1.80 C = RI 1.80 to 1.90 D = RI 1.90 to 2.00  \nFacets A B C D Index Instructions  \n\n| P1 | 43.35° | 43.35° | 43.35° | 43.35° | 02-06-10-14-18-22- | Form FCP |\n| --- | --- | --- | --- | --- | --- | --- |\n| G1 | 90.00° | 90.00° | 90.00° | 90.00° | 26-30-34-38-42-46- 50-54-58-62-66-70- 74-78-82-86-90-94 14-34-62-82 | Set stone size |\n| G2 | 90.00° | 90.00° | 90.00° | 90.00° | 13-35-61-83 | Meet G1, P1 |\n| G3 | 90.00° | 90.00° | 90.00° | 90.00° | 11-37-59-85 | Meet G2, P1 |\n| G4 | 90.00° | 90.00° | 90.00° | 90.00° | 08-40-56-88 | Meet G3, P1 |\n| G5 | 90.00° | 90.00° | 90.00° | 90.00° | 05-43-53-91 | Meet G4, P1 |\n| G6 | 90.00° | 90.00° | 90.00° | 90.00° | 02-46-50-94 | Meet G5, P1 |\n| P2 | 69.64° | 69.64° | 69.64° | 69.64° | 14-34-62-82 | Meet G1, P1 . Establish a level girdle |\n| P3 | 70.19° | 70.19° | 70.19° | 70.19° | 13-35-61-83 | Meet G1, G2, P2 & P1, P2 . Maintain a level girdle |\n| P4 | 70.82° | 70.82° | 70.82° | 70.82° | 11-37-59-85 | Meet G2, G3, P3 & P1, P3 . Maintain a level girdle |\n| P5 | 71.39° | 71.39° | 71.39° | 71.39° | 08-40-56-88 | Meet G3, G4, P4 & P1, P4 . Maintain a level girdle |\n| P6 | 71.73° | 71.73° | 71.73° | 71.73° | 05-43-53-91 | Meet G4, G5, P5 & P1, P5 . Maintain a level girdle |\n| P7 | 71.84° | 71.84° | 71.84° | 71.84° | 02-46-50-94 | Meet G5, G6, P6 & P1, P6 . Maintain a level girdle |\n\nCrown *A = RI 1.60 to 1.70 B = RI 1.70 to 1.80 C = RI 1.80 to 1.90 D = RI 1.90 to 2.00  \nFacets A B C D Index Instructions  \n\n| C1\u003Cbr>C2\u003Cbr>C3\u003Cbr>C4\u003Cbr>C5\u003Cbr>C6\u003Cbr>C7\u003Cbr>C8\u003Cbr>C9\u003Cbr>T | 59.46°\u003Cbr>34.41°\u003Cbr>60.20°\u003Cbr>61.06°\u003Cbr>61.84°\u003Cbr>62.30°\u003Cbr>62.46°\u003Cbr>31.12°\u003Cbr>25.92°\u003Cbr>0.0","cbCaivQuNRRyyihA","https://ap.wps.com/l/cbCaivQuNRRyyihA","pdf",639658,"English","# Pavilion facets and indexing\n## Facet sets by RI ranges (A–D) and instructions\n# Crown facets and indexing\n## Facet angles by RI ranges (A–D) and stepwise cutting notes","[{\"question\":\"What refractive index range does the Perception eye design support?\",\"answer\":\"The design is optimized for RI from 1.60 to 2.40, with separate angle tables grouped by RI intervals.\"},{\"question\":\"Why is the design not recommended for quartz?\",\"answer\":\"The author states the design will not optimize for quartz, and it is recommended instead for lightly saturated materials, especially at lower RI.\"},{\"question\":\"Which cutting accuracy points does the guide emphasize?\",\"answer\":\"The guide advises careful cutting of the C2 facets that are cut to depth, noting that the remaining crown facets should then fall into place.\"}]","Perception - Angle Tables for RI 1.60-2.40 - Free Eye Design | PDF",1792986024,13]