Bonhams 2017 Fall Jewelry Analysis: The $8 Brooch Sells

A busy weekend for me. Lots of auctions coming up but let’s finish our look at the auctions last week. I plan to make this a shorter analysis. I am not including a past auction of Bonhams to compare. Bonhams removes the unsold items from its list after the auction so if you do not gather your data before that then it is harder to get. My plan then is to focus on this auction only. I will look at the stats and percentage of sold versus unsold lots. Next, we will look at the top performing items and then look at the highlights from the post last week.

Sold versus Unsold

Note my results do not include buyer’s premium.

Looking at the table below you can see the percentage sold and unsold by category (type). There were 180 lots up for auction. The types are in order by highest percentage sold.

I also listed the total lots in each category so you get an idea how much was for sale. Watches did well but there were only 4. Same logic can be applied to the worst performing categories that only had 1 lot up for sale in that category. The category with the most items was the Ring category. From the Skinner analysis, we saw rings did well in that auction too.

Let’s dive a bit deeper into the items. Below is the table with the mean, median, and mode. I describe the significance of using these metrics in the Skinner analysis.

The lots ranged from $2,000 to $1,500,000 for the high estimate. So it is no surprise to see the average be so far off from the median and mode. Those higher end products can throw off the average. We see that most items were around $10,000 and sold at or slightly (10%) above the estimate.

Were there any outliers? What were the best performing lots?

Top 5 Lots

I like to look at the lots that outperform their estimates, not look at the lots that made the highest sale. Sometimes those are the same as we saw for that emerald brooch at Skinner. This time that was not the case. There were no major outliers. I created a table of the top 5 lots that were above their high estimate.

It is a good mix of designer and early 19th century that made the list. Below are the first 3.

Diamond and ruby line bracelet from 1925 was estimated to go between $5,000-$8,000. It sold for $20,000.

The emerald diamond ring sold for $22,000 and was estimated between $6,000-$8,000.

This fine diamond pendant from 1910 was thought to go between $8,000-$12,000 and sold for $28,000.

Past Predictions

So what about the items we looked at last week?

The wooden gold brooch by Cartier…

and the black opal that was estimated around $300,000.

Both went unsold. I was surprised about the brooch, it was estimated between $10,000-$15,000. Which I did not think was that bad.

Now to the final piece the story of the yard sale brooch bought for $8 and sold for…

$21,000. Bonhams predicted that right. They estimated getting between $20,000-$30,000.

All photos courtesy of Bonhams.

What are your thoughts on this auction? Do you agree with my findings? What was an item you were watching in this auction? The coming week is going to be fun! I will look at two celebrity auctions based in London. Check back this week for more on Data in the Rough!