GemTec (Ex Hwa-il Machinery Co.), established in 1959, has specially been producing and supplying equipment, tools and its accessories related with the works of rock, lapidary, hot-fix rhinestone, jewel & diamond, which are necessary for cutting, grinding, polishing, cleaning, thin section & epoxy mold manufacturing, etc. of raw materials, handiwork and appraisal, and has been supporting educational institutions and organizations about the information, training & installation of equipment and tools. 

Thin Section Manufacturing Service (or Making Service) (薄片作製サービス)


Please click here or the below photo for the details of the thin section manufacturing (or making) service



Manufacturing Epoxy Resin Molds for Metal, Mineral Grains & Fossil, Rock Chips


 < Epoxy Molds of Metal, Mineral Grains & Fossil, Rock Chips > 

                < Epoxy Molds with Tags>                     < Epoxy Molds in Box > 

  • The metal, mineral grains and fossil, rock chips will be molded by the epoxy resin injected after the air in the grain or the chip is removed in the vacuum chamber.
  • Manufacturing the complete molds according to the method veriifed by the research institute.
  • Polishing the grain or the chip with diamond powder (1/2 or 1/4 micron) at the finishing stage.

Service for Regional Lithological Mapping of Naturally Occurring Asbestos


We GemTec had manufactured the rock thin sections with participating in the following research project according to the contract with the Korean Society of Economic and Environmental Geology:

  • The title: Service for Regional Lithological Mapping of naturally occurring asbestos (Rock thin section manufacturing service for researching the mineral characteristics of the ground and the estimation of naturally occurring asbestos)
  • The term: Nov. 20, 2014 ~ Nov. 19, 2015

GemTec signed Industry-Academy Cooperation Program  


Survey Trip to Electrolytic Copper Cathodes Companies



The  First Public Opening of Hot-Fix Rhinestone Manufacturing Process



Successful Completion of the Factory Trial for Asfour Crystal


We celebrate the successful completion of the factory trial for hot-fix rhinestone manufacturing process including technical instruction to Asfour Crystal, Egypt.

New Order for hot-fix rhinestone machines

GemTec received an order for hot-fix rhinestone machines worth $1.5 million from Asfour Crystal, Egypt,  prominent high-quality crystal producer on August 11.

Selected as one of the "Recommended Companies"


GemTec proudly announces that it has been selected as one of the "Recommended Companies" by KOREAN MARKETPLACE which is created by Small & Medium Business Administration(SMBA) and Small Business Corporation(SBC) of Korean Government.

3rd Shipment of Hot-Fix Rhinestone Machines for Turkish Factory


We celebrate the 3rd shipment of hot-fix rhinestone machines for Turkish factory.





Liaison office in the Netherlands/Egypt


Gemological Institute


Thorough A/S !!


Gemstones & Jewelry

Gems Corporation


Internet Sales
Diamond & Jewelry

Brazil Plus Gems & Minerals Ltda.

Gemplus Corporation Ltd.  


Amethyst & Citrine for Faceting 


Changsha Xinye Industrial Corp., Ltd.


Synthetic Diamond

Kam Technology Corp. 


Nitrides, Borides, Carbides & Inter -Metallic's 

Luoyang New High Technology Qiming Superhard Material Co.,Ltd. 


Synthetic Diamond


Cubic Zirconia(CZ))

Cost Saving via Best Quality & Lowest Price

Package of 108 gems & semi-precious stones
with certificates

Emerald & Diamond

Natural Brazilian Emerald & Diamond stones!


[Glass Processing]  Hot Fix Rhinestone Machine


1. GLASS FURNACE (is used for glass powder (silica powder) mixing, melting, pattern making and sorting of hot fix rhinestones.)
2. GRINDER & POLISHING MACHINE (is used for resin bonding, resin hardening, polishing and hot fix grinding of hot fix rhinestones.)
3. VACUUM COATING MACHINE (is used for aluminium coating of hot fix rhinestones.)
4. BONDING WORK MACHINE (is used for bonding and hardening of nylon powder to hot fix rhinestones.)
5. HOT-FIX ROLL (is used for rolling-over of hot fix rhinestone stones.) 

[Rock Processing] Ring Mill  


  • For crushing rock materials to regular size
  • Tightness type to minimize dust generation
  • Pan for powder collection
  • Adjustable of inlet gap according to rock size 

[Rock Processing] Ring Mill  


  • For crushing rock materials to regular size
  • Stainless steel drawer for powder collection
  • Safety cover

[Rock Processing] Gem & Rock Saw


  • For making thin slab
  • Attachment of material by vacuum after bonding to slide

[Rock Processing] Rock Core Precision Machine


[Rock Proces.] Desk-Top Type Core Drill Machine


[Rock Processing] Compressor Soundproof Case


  • Noise minimization of indoor working place
  • Ventilation fan to expel heat

[Handiwork] Furnace


[Rock Processing] Thin Section Working Table


[Rock Processing] Small Magnetic Susceptibility Meter



  • 1 x 10-7 SI units
  • 9 kHz
  • 4 digits LCD
  • 100 x 65 x 25 mm
  • 0.180 kg
  • RS232C
  • ZH Instruments Make




Gem Care


Cautions and tips for gem care, quoted from The Handbook "Gem Care" - Korean language is only available.

[Cut & Treatment] 


Pebble Dyeing  - Korean language is only available.


Explanation on how to dye pebbles

[Cut & Treatment] 


The Optics of Brilliant-Cut Diamonds


By W.R. Eulitz
The foremost intention of this paper is to clarify the physical principles that determine the effect of any cut stone including diamond.
(Note : This article is located at the section of "relevant data" in Korean Home)



Table of Properties of Gemstones


In order of the figures of composition, hardness, specific gravity, reflective indices & birefringence - Korean language is only available

Office: Rm No. 602-74, 105, Jungdong-ro 248 beon-gil, Bucheon-si, Gyeonggi-do, Zip Code 14548, Korea
| TEL: +82 (0)32 323 0862 | FAX: +82 (0)504 429 7706
Factory: 538-7, Opo-Ro, Gwangju-Si, Gyeonggi-Do, 12774, Korea
TEL: +82 (0)31 766 0862 FAX: +82 (0)31 766 0863

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