Quality control

2nd April 2024 - Customer location: Cairns

Some “matching” gems purchase by a customer overseas on a holiday

I am going to share today with you the process of me sourcing a very special piece of Tanzanite to be set into a ring. Before that I want to explain a bit about what I look for in gems as I search for customers. To do this I want to first show you some gems a customer sourced on their own.

The above gems were purchased on an overseas trip by a customer and were presented to me about 4 years ago to be set into a ring. I had to give her the very bad news of the flaws in the gems that she had not noticed in the excitement and rush of the purchase.

Article: The jeweller swapped my diamond

I did not spend much time cleaning these gems for the photos but you should be able to firstly see that the colours do not match.

The surface of the gems are poorly polished with many scratches and chips visible. In the photo on the right you can see what looks like sweating on the surface of the gems. Most sapphires are heat treated to enhance their colour and I think this may be a result of something going wrong with that process..….but that is speculation as I am a jeweller not a gem cutter.

The final point with the gem on the right is that the left side is shorter than the right and the top edge is curved. It is hard to make a non square gem look square in many styles of setting and designs.

Once I pointed out these issues the ring make was cancelled as the customer no longer valued the gems. I would never source gems like this for a customer no matter how inexpensive they were.

Some gem types are always flawed

The flawed world of even high grade natural Emeralds.

Natural Emeralds are a very good example of a gem that is almost always heavily flawed and for me that is part of the beauty of a natural Emerald. That said, aside from minimising flaws we can always look to set a high standard for the shape and cut of the gem.

With natural gems most have some sort of flaws present. It is my job when I source them to make sure that the customer is aware of any flaws present and that unnecessary ones are as much as possible absent.

Time for me to find a gem for my customer

The CAD render used as a starting point for the design.

With that introduction into some of the issues I face when sourcing gems I would like to share with you the process of making the above design. The ring parameters were to be as follows:

  1. Emerald cut Tanzanite

  2. About a 4 carat gem

  3. 18ct rose gold band

  4. 18ct white gold setting

  5. Trapezoid shoulder diamonds


Checking to see of the size gem she thought she wanted was right

Checking the size of a 4 carat gem on the hand.

The first task was to make sure that the 4 carat size the customer had in mind would look on her hand how she thought it would. I have used a CAD generated hand in the photos above but with the customer we used an actual photo of her hand.

Showing variations in the main gem and shoulder diamonds.

We would repeat this process many times as I found gems in the size and colour range that inevitably were all a different shape. Some longer, some wider etc.

Thought we had found the right gem :(

Two gems submitted to me by a broker.

When I submitted the photo of the above gems to my customer she immediately fell in love with one of them. It was now time for me to have a deeper discussion about the gem with the broker.

A chip at the base of the gem.

In one of the photos of the gem sent to me I noticed something visible from the front. I asked the broker to email me more photos in particular of the back and sides. On viewing those photos I discovered what I was seeing from the front of the gem through the table, a chip at the base.

I asked her if that was a speck of dust (photo taken with a phone I assume) or a chip. She advised me that it was indeed a chip and also that recutting was not an option as too much weight would be lost. Being a very expensive gem I informed my customer of the situation and rejected the gem.

It is not uncommon for brand new gems to have chips, especially easily damaged gems such as Tanzanite, Amethyst etc.. These chips can be a result of poor finishing, handling or storage but unless they are of an acceptable level I reject them.

In the case of this very expensive gem spotting this issue before it was sent to me saved myself and the broker the time and expense of sending/returning it. The search for a gem continued!

……….about a month later!

Could this be the right gem?

For the next month I spoke to pretty much every gemstone broker in Australia to see if they had a suitable Tanzanite with no luck.

Some had even promised to look for a gem next time they went overseas on a buying trip. Then a broker who initially told me he did not have a suitable gem emailed me a photo of the above stone. It looked very promising.

You may be thinking there must be an abundance of Tanzanite gems all over the world for sale. There might be but I need gems from Australian brokers that can be sent to me for approval by my customers and readily returned if rejected.

Photos no matter how well they are taken, no matter how colour calibrated the viewing screen is can look different in a photo to real life. Seeing is believing and returning gems that do not live up to the photos to overseas brokers is a nightmare and expense I will not endure.

The gem was sent to me and it was indeed spectacular and one of the best finished gems I have seen. The cut and finish were to the highest standard…..and I knew it would probably be so because the broker told me he cut the gem himself.

Now to find the shoulder diamonds

Step cuts on the left and brilliant cut on the right.

With the Tanzanite gems size now confirmed I could start trying to find the shoulder diamonds to match the design. The diamonds to go on the shoulders of the ring are Trapezoid cut which refers to the shape of the outer border.

The internal facets of the pair on the left above are what we call a “step cut” and on the right “brilliant cut”. The customer desired a pair of brilliant cut Trapezoids. I now had to find two of these diamonds in these parameters:

  1. good pair

  2. approx 4.5mm on the longest edge

  3. brilliant cut

  4. minimum E colour and Vs clarity grades

After quite a few more phone calls I found a nice pair with a Melbourne diamond broker. Unlike other gemstones once diamonds have a colour and clarity grade (and I have seen photos for clarity) I know what to expect. We could now start putting the finishing touches on the design.

Time to finish the design

Scroll gallery work.

This ring was being made as a reminder of a late relative. To add a special touch to the ring rather than do the classic plain double rail side we came up with the scroll work above. The customer loved the image :)

Double checking the finger size and design = make a draft

The base of the draft ring resized to the perfect size…so that the actual ring did not have to be.

I was now ready to make a draft of the ring so that the customer could get a hands on feel for it before it was made. The draft is made in scrap silver and roughly finished but gives a very good representation of the shape of the finished ring. If we needed to make changes we could confirm them now.

We also manipulate (resize) that draft until the ring size was the perfect fit. I definitely did not want to be resizing this brand new ring.

Article: Why you should avoid resizing a new ring

With the design approved and the ring size confirmed I was ready to make the ring. Everything was in place.

The finished result

4.37 carat emerald cut Tanzanite (Merelani) - 2 x .10ct Trapezoid cut diamonds.

This ring was created for a longtime customer. Since meeting them I have been fortunate to make jewellery for their children as well over the years. It will be one of the most memorable makes of my career for reasons you may not expect.

The first reason is that the Tanzanite is one the best finished gems I have ever seen in a beautiful colour. It is truly stunning! Next the trapezoid diamonds were a great pair and like the Tanzanite they were also extremely well cut which made setting them much easier. It took a while but we got the gems near perfection and that does not happen very often in this world of shrinking local suppliers and stock.

18ct rose and white gold setting.

The band was created in an 18ct rose gold formula that I personally developed with a precious metal refiner many years ago and remains to this day one of my favourite gold alloys. The icing on the cake was the extra touch of that old world gallery……and of course that the customer adores the ring.

Design, Info, RingsDavid Taylor