Green Manufacturing

Green Manufacturing at G&S Jewelry Mfg

Remember when you were a kid and someone would ask you: “What’s your favorite color?” At G&S Jewelry Mfg we have many favorite colors, but we all agree that we love green; as in green manufacturing!

Our Focus

Being that we live in the beautiful, but dry New Mexico climate; water is always a concern. From drought conditions in the worst of years to the normal low humidity, water is always at a premium.


Our Process Technology Roadmap

Because we are an investment caster; our technology roadmap shows water employed in four main areas:

First, water is used to mix with dry Ransom & Randolph investment. Rinsing the mixing machine completes this operation.

Secondly, water cools our vacuum induction casting systems.

Third, we use high pressure water in a blasting cabinet to devest the castings to remove the investm

Fourth, rinse water for tumbling operations to rinse the parts and the media.


Our Remedies

Investment Water – Pumping rinse water to a separation tank using a double diaphragm pump.  The solids settle and the water is filtered for reuse.

Casting System – Acquisition of a recirculating system from Rio Grande.  Water management problem is resolved by delivering cooling water at a consistent temperature and flow rate. At this time we are contemplating purchasing an additional unit for other cooling application. These systems immediately reduce water consumption to nearly zero.

Cooler Mounted on J15 225x300 Green Manufacturing
RC6 Cooler Mounted On J-15 Automatic Vacuum Casting System

Devesting – Generally speaking devesting is the least technical water requirement. Our blasting cabinet is located adjacent to our casting and tumbling areas. Therefore, plumbing of recycled water from a filtered source is simplified.

Serial Filtration 225x300 Green Manufacturing
Removal of Solids From Process Water

Tumbling Operations – Installation of a rinsing part separator with a closed loop water system.

Neutec Wet Part Media Separator e1493575689340 225x300 Green Manufacturing
Neutec Wet-Media Flow Separator


Summing up; Green Manufacturing is good for the environment and results in more “Green” wallet share.  Hence, this is a key part of G&S Jewelry Mfg commitment to sustainable manufacturing. In the long run it is the best for our customers and our industry!

The Importance of Vacuum Investment Casting

Vacuum is a very important condition for Investment Casting. G&S Jewelry Mfg employs two methods of vacuum investment casting. The first being a closed chamber inert gas automatic casting design. The second is an open air pouring system for large bronze castings.

Vacuum Investment Casting – The Why’s & How’s

Both of these systems employ a vacuum pump to draw the metal to the deepest extent of the mold as possible. The former uses an enclosed system with a perforated flask, while the latter employs a vacuum table with a solid sided flask.  The photo below expressly illustrates the difference.

Flask Comparison 300x225 The Importance of Vacuum Investment Casting
Perforated and Solid Side Flasks


Another key point is the interaction of vacuum and gravity. Because gravity pulls the molten metal when poured.  Vacuum further accelerates the draw of the metal.   With this in mind the combination of these forces will achieve the best possible fill.

Casting Systems – Enclosed vs Open

Rio Grande Neutec J 15 Enclosed Chamber Vacuum Investment Caster e1494782801764 225x300 The Importance of Vacuum Investment Casting
Enclosed Chamber Neutec J-15 Caster


Vacuum Chamber for Neutec J 15 Caster e1494784158823 225x300 The Importance of Vacuum Investment Casting
Sealing Vacuum Chamber for J-15 Above

G&S Jewelry Mfg uses two types of casting systems. An enclosed chamber automatic caster as shown in the two photos above and an open air pouring system as shown below.

Rio Grande Vacuum Table 300x225 The Importance of Vacuum Investment Casting
Vacuum Table for Open Air Pouring

Obviously the difference between the two systems is easy to point out. Inasmuch as some metal tolerate oxygen better than others, the key point is the negative pressure on the flask to draw molten metal. Depending upon vacuum quality and metal superheat, the draw may draw more liquid metal during the period of shrinkage. Shrinkage occurs as the metal changes from the liquid to solid state.

In Summary

Placing a perforated or sealed flask under negative pressure delivers superior casting. Let us work with you to deliver the best possible jewelry castings. This process meets our 100% commitment to sustainable manufacturing. Please contact us here  for more information.

G&S Jewelry Mfg is a small woman owned business with 100% of our facilities in the U.S.A.


Insight on Copyright Law For Jewelry Designers

Copyrighting is an important tool for jewelry designers to protect the product of their imagination and their hands. This protection is available to designers of both large and small companies; even those companies composed of a single person. It is a common misperception that copyrighting is time consuming and very expensive. It can be both of course, but knowledge of the process and requirements will significantly reduce both time and costs.

The copyright extends to handmade designs, handcrafted pieces, investment cast components or any combination that delivers a tangible part. You have spent your creativity, time, sweat and effort to design something unique. YOU own it, protecting it is important. Copyrighting is an excellent means of accomplishing this.

Ryan Wityak has written an excellent summary of the process; it is listed below. Ryan is an attorney at Peacock Myers PC and a part owner of G&S Jewelry Mfg. If you have any questions as to what is covered; he can be reached at:

Peacock Myers PC

Office Phone: (505) 998-6124


Copyright Law Distilled for the Jewelry Designer and Manufacturer

Impact of Oxides in Jewelry Investment Casting

By its nature; investment casting requires predictable filling and flow of molten metal to the extent of the design in the mold. Solidification occurs on the interior surfaces of the mold a progresses inward and upward towards the molten stream source. Ideally any porosity that occurs will be inside or off the piece away  from the surfaces desired for finishing.

To achieve this, it is important that the metal being cast be of uniform composition and consistent in terms of cleanliness and oxygen levels. Dirt or oxide inclusions can inhibit flow of the liquid metal and create two types of defects in the castings. The first being areas where the inclusion will be present on the surface of the piece creating an area that will not polish or breaks out of the surface leaving a hole that needs to be repaired. The second is where the dirt or oxide particle wedges into a via in the mold and prevents metal from flowing down that via to complete the filling. This can be seen in areas where fine detail texture or filigree is interrupted. In these cases the part is likely not repairable and needs to be recast.

The conditions for successful casting require good metal sourcing, care in casting and good process control when recycling scrap. Most casting grain suppliers can meet oxygen demands for sterling investment casting. Use of graphite crucible equipped automatic casting systems with a neutral or slightly reducing cover gas will prevent oxygen from entering the melting stage of the process during casting.

For those casting systems equipped with a window that allows for observation of the melt during melting, the surface of the melt should be clean and lack any white, frosty dross on the surface. Highly reflective surfaces with little or no reaction with the wall of the graphite crucible means that oxygen numbers are low.

A good vacuum seal during the cast process will prevent introduction of oxygen during the flow of metal part of the process. However, when vacuum is broken and the flask is removed from the vacuum chamber, oxygen from the convection cooling in air of the flask will blacken the surface of the tree in whole or in part. Ways to mitigate this include immediate quenching or use of a cover material to scavenge oxygen during cooling prior to quenching.

A good pickle of the tree especially the button will reduce the oxide level of the surface. The sprue and tree scrap can then be regrained in reducing atmosphere to get as much oxygen out of the scrap prior to reuse. Using a melt make-up of 50% max remelt should be successful in keeping oxide levels down to an acceptable level. Higher amounts of virgin metal can be employed as dictated by part design and tribal experience. The skilled staff at G&S Jewelry Mfg is particularly versed with the requirements for successful casting.



Types of Finishing of Investment Cast Jewelry Components

There are many options for investment cast jewelry components. These include several different types of mass finishing as well as hand finishing techniques. Each have their place depending upon the desired reflectivity, contrast or directionality of the lines of finish texture.

Mass finishing is most commonly employed as it offers low cost, consistency and high quality. It is accomplished in barrels or bowls with wet or dry media. The finish returned can range from a matte finish to a highly specular finish. The level of finish is dictated by the media used, the amount of time of finishing and the stages used for finishing.

Matte finishing can be accomplished using a coarse media dynamically applied enough to remove the rough areas of the casting. This leaves a surfaces that is clean and omnidirectional with no texture lines in the piece. Adding one or two more tumbling steps using finer and harder media will further brighten the surfaces as the peaks and values of the surface become smaller and smaller. Finishing in a ceramic media using a suitable liquid medium to suspend the fine particles will return a highly polished surface.

In the Southwest, many designers want their pieces to have a look that gives the appearance of being worn for many years. In order to achieve this, G&S Jewelry Mfg has developed a technique to deliver a “chaotic” surface with scratches in the surface in random directions. The result is a brand new piece that looks like it has been hard at work for years!

Hand finishing is done on a piece by piece basis. The skill of the buffer along with the media used is critical in achieving the desired look. There are several options here to choose from. Most common is a highly polished surface with bright omnidirectional surfaces on all areas. Alternatives are satin finishes with or without directional texture. A directional texture has a brushed look, all lines of the surface are somewhat parallel. These are most commonly requested for long smooth surfaces such as bracelets.

Hand finishing is more costly due to the labor involved but has it placed depending upon the look desired and customer appetite for the design. G&S Jewelry Mfg is happy to work with its customers to develop the processes that will meet their expectations for color and appearance.

Extending Your Designs for Increased Return on Investment

One of the best ways for a jewelry designer to succeed is to extend successful designs into other components. Consider the following: A piece such as a particular pendant design has been selling well and market acceptance is expected to grow. Taking this basic design and extending it to other complementary components such as earrings, rings, bracelets and charms will increase the return on that design. Why not? You own the design and spent precious time developing it and producing first articles. Redesigning the part and retasking it for other components makes good business sense particularly if the design is in digital format and you have the contact information for current pendant customers to test market the designs.

Digital formats can readily be shrunk, stretched and modified for mounting in a variety of ways. The volumes will be returned and the articles can be priced in many different materials so that the delivered price can be understood in a very straightforward manner.

Customers that have purchased the present design can be offered accessories or sets to match. These customers will be a very good barometer as to market acceptance. The cost to the designer is low compared to the first design, extending good selling designs will broaden your portfolio and add to your bottom line.

Pro Forma Cost Analysis

One of the frequent comments we receive from customers is that the product costing is challenging when starting with a new or existing design. In response we generally suggest developing a pro forma cost analysis based upon several key attributes of the design. This can be done for one material or for several materials to evaluate the costs of a design prior to manufacturing a single piece.

The key attributes will be:

Part Volume

One Time Charges (e.g. Mastering, Molding, Silversmithing)

Material(s) Desired for Part Production


Secondary Operations

Part Volume – If we consider that a part will weigh x number of grams in sterling or y number of grams in karat gold or z number of grams in bronze, the differences in intrinsic raw material costs between these three materials will be distinct. Thus the volume of the piece will be a significant part of the cost.

One Time Charges – These charges are for any mastering, molding or silversmithing required to make the design ready for wax injection. These costs are generally the same for sterling, karat gold or bronze and can be pro rated over the life of the design.

Material Selection – As mentioned, the materials under consideration will have a significant impact on cost due to the intrinsic cost of the alloy. Building a cost matrix denoting the prices of each material is very helpful when developing sell price model based upon intended markup and sales channels.

Quantity – Quantity is an often overlooked element as most if not all processes follow a natural logarithm pattern for costs. Higher volumes will generally allow for some cost savings.

Secondary Operations – These steps can include hand buffing, plating, assembly or setting. Depending upon the requirements, it is important to understand the impact on the final cost of the piece. Some operations such as plating lend themselves to mass processing, whereas hand buffing is much more labor intensive. Breaking these costs out help in decision making as to the value of these steps based upon target price of the product.

Summary – A spreadsheet can be readily constructed that will incorporate all of these cost contributing line items into an easy to understand. What-if? scenarios can be entered and the results compared to get close to the target price goals. This aspect of the pre-production planning can mean the difference between good margins or razor thin margins in the final product.



Vacuum Investing for Improved Casting Surfaces

Investing your flasks and using vacuum to draw bubbles out of the slurry is a key component in successful investing. In this scenario, the investment is poured into the flasks and the investing chamber isolated by closing off all openings to the chamber open to atmosphere. A vacuum pump plumbed directly to the investing chamber is then started to create a negative pressure over the top of the open flasks. Observing the surface of the slurry in the flasks, bubbles can readily be seen to rise to the top and pop. The surface will continue to bubble as trapped air is released and the slurry becomes more dense. This means that the slurry will now conform more closely to the surface of the wax pattern inside the flask. The result will be fewer voids and smoother surfaces. The photo below shows an empty flask on a turntable below a tap used to pour investment slurry into the flask. The plexiglass lid seats on a rubber seal on the rim of the stainless steel chamber. When vacuum is applied the lid seals and the inside of the chamber is under vacuum.

Robotech Vacuum Investing System 300x225 Vacuum Investing for Improved Casting Surfaces
Flask on Turntable In Investing Chamber Beneath Plexiglass Chamber Lid For A Robotech Investing System



Valentine’s Day Is Less Than A Month Away!

Yes, Christmas is over but Valentine’s Day is right around the corner! G&S Jewelry can produce one of a kind or mass production of virtually any ring, bracelet or pendant. Challenge us with what you want!

We also have a wide variety of Valentine’s themed items in our catalog. Check our Rings and Bracelets in Our On-Line Catalog.

G&S Jewelry Mfg is a small woman owned business with all of our manufacturing right here in the USA.

Automatic Casting Machines for High and Low Volume Production

Casting quality is always a concern for any customer. There are many factors that can impact quality. These include:


Part Design

Metal Selection

Metal Quality

Metal Casting Temperature

Flask Temperature

All of these factors whether singularly or in a compounded manner will impact quality. As a manufacturer we seek solutions that will address as many of these factors with high levels of repeatability. Automatic systems that can be programmed and monitored significantly reduce variability and are an excellent addition to a caster’s production suite of equipment.

Reviewing the list above, an automatic casting system will impact metal quality and metal casting temperature directly. Because most automatic casting systems have controlled atmospheres above the melt and frequently use graphite crucibles, metal quality is very stable. Oxygen is removed or levels stabilized by inert gases and reaction with the wall of the crucible.

Automatic systems have temperature controllers that bring the metal up to a preset temperature and will cause the metal to cast into the mold if programmed for automatic release. Most automatic casters are equipped with timing sequences for removal from the flask after a period of solidification. This further protects the metal from oxygen pick-up during the critical liquid to solid phase change of the metal.