Final:
The first pearl dealer's nervous habit is constantly twirling a strand of pearls around his fingers.
Step-by-step explanation:
As a professional pearl dealer, meeting potential clients and showcasing his merchandise can be a nerve-wracking experience. To alleviate his anxiety, the dealer has developed a nervous habit of twirling a strand of pearls around his fingers. This habit serves as a calming mechanism, allowing him to focus on the task at hand and appear more confident to his customers. Additionally, it may also help him to better appreciate the beauty and value of the pearls he sells, as he becomes intimately familiar with their texture and weight. However, it's important for the dealer to be mindful of this habit, as excessive fidgeting could potentially damage the pearls or distract potential buyers during negotiations.