Gemological and Spectral Characteristics of Gem-Quality Blue Gahnite from Nigeria

<table class="table-group" id="tab3"><tr><td><table class="table"><tr><td class="thead-hr" colspan="6"><hr/></td></tr><tr class="thead"><td class="align_left" rowspan="2">T<sub>1u</sub></td><td class="align_center">Gahnite</td><td class="align_center">Gahnite</td><td class="align_center">Gahnite</td><td class="align_center">Gahnite nanopowder</td><td class="align_center" rowspan="2">Assignment</td></tr><tr class="thead"><td class="align_center">This work</td><td class="align_center">[<a href="/journals/jspec/2024/6693346/#B6" target="_blank">6</a>]</td><td class="align_center">[<a href="/journals/jspec/2024/6693346/#B12" target="_blank">12</a>]</td><td class="align_center">[<a href="/journals/jspec/2024/6693346/#B8" target="_blank">8</a>]</td></tr><tr><td class="thead-hr" colspan="6"><hr/></td></tr><tr><td class="align_left"><span style="width: 10.9702ptpx;"><svg height="9.32509pt" id="M2" style="vertical-align:-3.1815pt" version="1.1" viewbox="-0.0498162 -6.14359 10.9702 9.32509" width="10.9702pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><g transform="matrix(.013,0,0,-0.013,0,0)"><path d="M213 67C239 136 257 225 255 300C253 353 242 447 164 447C112 447 54 389 41 319L67 309C90 362 117 377 134 377C184 377 189 277 190 239C193 153 164 43 146 -12H176C278 73 450 253 450 390C450 439 410 463 396 463C384 463 380 459 382 449C385 440 389 415 389 402C389 284 312 146 216 67H213Z"></path></g><g transform="matrix(.0091,0,0,-0.0091,5.902,3.132)"><path d="M389 0V32C297 38 291 46 291 118V635C234 613 175 595 109 583V556L161 554C203 552 207 547 207 497V118C207 46 201 38 110 32V0H389Z"></path></g></svg></span></td><td class="align_center">510</td><td class="align_center">505</td><td class="align_center">505</td><td class="align_center">498</td><td class="align_center">Zn—O</td></tr><tr><td class="align_left"><span style="width: 10.9702ptpx;"><svg height="9.32509pt" id="M3" style="vertical-align:-3.1815pt" version="1.1" viewbox="-0.0498162 -6.14359 10.9702 9.32509" width="10.9702pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><g transform="matrix(.013,0,0,-0.013,0,0)"><path d="M213 67C239 136 257 225 255 300C253 353 242 447 164 447C112 447 54 389 41 319L67 309C90 362 117 377 134 377C184 377 189 277 190 239C193 153 164 43 146 -12H176C278 73 450 253 450 390C450 439 410 463 396 463C384 463 380 459 382 449C385 440 389 415 389 402C389 284 312 146 216 67H213Z"></path></g><g transform="matrix(.0091,0,0,-0.0091,5.902,3.132)"><path d="M414 144C384 79 371 75 317 75H135L276 221C367 316 408 376 408 465C408 570 327 635 237 635C179 635 131 609 100 575L42 494L67 471C94 510 138 565 205 565C277 565 321 517 321 435C321 348 258 270 195 195C146 137 88 81 33 26V0H411C423 44 433 88 446 135L414 144Z"></path></g></svg></span></td><td class="align_center">559</td><td class="align_center">550</td><td class="align_center">560</td><td class="align_center">573</td><td class="align_center">Zn—O</td></tr><tr><td class="align_left"><span style="width: 10.9702ptpx;"><svg height="9.4347pt" id="M4" style="vertical-align:-3.29111pt" version="1.1" viewbox="-0.0498162 -6.14359 10.9702 9.4347" width="10.9702pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><g transform="matrix(.013,0,0,-0.013,0,0)"><path d="M213 67C239 136 257 225 255 300C253 353 242 447 164 447C112 447 54 389 41 319L67 309C90 362 117 377 134 377C184 377 189 277 190 239C193 153 164 43 146 -12H176C278 73 450 253 450 390C450 439 410 463 396 463C384 463 380 459 382 449C385 440 389 415 389 402C389 284 312 146 216 67H213Z"></path></g><g transform="matrix(.0091,0,0,-0.0091,5.902,3.132)"><path d="M290 377C321 398 342 415 358 430C378 450 389 473 389 502C389 578 329 635 238 635H237C184 635 137 610 109 578L64 515L88 493C112 529 154 573 208 573S303 542 303 482C303 409 233 370 141 341L149 308C165 313 190 319 215 319C272 319 341 283 341 193C342 98 292 43 222 43C163 43 122 72 96 94C88 101 79 100 70 94C61 87 47 73 46 60C44 47 48 37 62 23C76 10 118 -12 165 -12C238 -12 430 62 430 223C430 297 379 359 290 375V377Z"></path></g></svg></span></td><td class="align_center">664</td><td class="align_center">660</td><td class="align_center">665</td><td class="align_center">658</td><td class="align_center">Al—O</td></tr><tr><td class="align_left"><span style="width: 10.9702ptpx;"><svg height="9.32509pt" id="M5" style="vertical-align:-3.1815pt" version="1.1" viewbox="-0.0498162 -6.14359 10.9702 9.32509" width="10.9702pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><g transform="matrix(.013,0,0,-0.013,0,0)"><path d="M213 67C239 136 257 225 255 300C253 353 242 447 164 447C112 447 54 389 41 319L67 309C90 362 117 377 134 377C184 377 189 277 190 239C193 153 164 43 146 -12H176C278 73 450 253 450 390C450 439 410 463 396 463C384 463 380 459 382 449C385 440 389 415 389 402C389 284 312 146 216 67H213Z"></path></g><g transform="matrix(.0091,0,0,-0.0091,5.902,3.132)"><path d="M462 177V227H365V632H320C217 496 116 350 21 208V177H284V109C284 43 280 38 190 31V0H451V31C369 38 365 43 365 108V177H462ZM284 227H88C155 336 218 430 282 519H284V227Z"></path></g></svg></span></td><td class="align_center">—</td><td class="align_center">—</td><td class="align_center">745</td><td class="align_center">813</td><td class="align_center">Al—O</td></tr><tr class="table-tr"><td colspan="6"><hr class="tbody-hr"/></td></tr></table></td></tr></table>

<div>Infrared spectral absorption wavenumber (cm<sup>−1</sup>) comparison of gahnite.</div>

Journal of Spectroscopy

tab3

Table 3

Table 3: Gemological and Spectral Characteristics of Gem-Quality Blue Gahnite from Nigeria 